Dress IV: Keli Gever

  • Deracheha Staff; Laurie Novick, Director
By Laurie Novick
Rav Ezra Bick, Ilana Elzufon, Shayna Goldberg, and Sarah Davis Rudolph, eds.
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Defining a Keli Gever
We opened this series on dress by identifying some essential functions of clothing, including covering erva and dignifying the individual. Here, we discuss another possible function, representing gender.
The Torah takes it as a given that men's and women's dress differ in at least some respects, and prohibits a man from wearing "simlat isha," a woman's garment, and a woman from having "keli gever," a male article, upon her:
Devarim 22:5
A man’s article shall not be on a woman, neither shall a man wear a woman’s garment; for whoever does these things, it is an abomination to the Lord your God.
Though these are counted as two distinct mitzvot, the parallelism within the verse means that they are usually taken as a unit. Even so, we will focus our discussion on a woman's prohibition, drawing on a man's prohibition only insofar as it adds to our understanding of keli gever. We'll explore what is considered a man's article, the permissibility of gender-neutral clothing, how the prohibition is defined, rationales for the prohibition, and the significance of intent.
What makes something a man's article or, for that matter, a woman's garment? What type of item is considered a keli gever? Given the wide variation in norms of dress in different locales over history, it would be difficult to argue that the definition of keli gever is absolute and unchanging. Indeed, Rambam rules that the definition of what constitutes a male or female garment depends on local norms:
Sefer Ha-mitzvot of Rambam, Negative Commandment 39
Any woman who decorates herself in one of the known male ornaments in that city, where this ornament is unique to men, receives a punishment of lashes [for violating a Torah-level prohibition].
Many other halachic authorities, including Tur, Shulchan Aruch, and Rema, adopt the view that male and female garb are defined based on local practice:
Tur YD 182
A woman should not wear garments unique to a man in accordance with local custom…
What is local custom? A ge'onic responsum cited by Rashba establishes that halacha recognizes the prevailing dress norms of a given time and place, and takes non-Jews into account as part of the context for understanding Jewish norms of dress. (This responsum also references men undertaking feminine grooming practices as falling under the man's prohibition, a point to which we'll return later.)
Responsa of Rashba V 121
For Rav Sherira and his son Rav Hai…There is a distinction among women's ornaments, between times and places. There is also a distinction among different garments. For thus they practiced here, that clothes of linen and clothes of cotton, men don’t wear them dyed. But clothes of silk and clothes of fine wool, men wear them dyed, in all kinds of colors. Therefore, it is permissible for them to wear these, in accordance with the custom of time and place. And if there were a time or a place where they are not accustomed to these either, these would be prohibited to them. And thus, for here there is a custom of women's clothing and of men's clothing, and in other places a different custom, its whole prohibition is in accordance with its custom, and the permission is in accordance with its custom. For what is a man's or a woman's garment is only defined for us in accordance with the customs regarding [the garments], in those years…In Arabia there are those who are descended from Ishmael and Yaktan whose custom is thus: that the man who removes his armpit and pubic hair, they see him as weak as women. And [Jewish] men of these places now, it is prohibited for them to remove their armpit and pubic hair…
The Ge'onim note that there does not seem to be a universal or objective Jewish standard for men's or women's dress aside from current practice, though they presumably require dress to meet the parameters of tzeniut. They add that there is no prohibition on a person taking up a mode of dress common to men and women in a given society. (We'll discuss this possibility further in our section on gender-neutral clothing.)
However, the approach of the Ge'onim troubles Rashba. He hints in an earlier teshuva that certain acts of grooming are more independent of local norms. In this responsum, Rashba cites a Talmudic story in which a man's unshaved armpits indicate that he is more meticulous in observing halacha than the general population.[1]
Responsa Rashba IV:90
…For the Torah did not say, you shall not remove armpit or pubic hair, but rather in general cautioned us against everything that is the manner of women. And that is what is written in a general way: A man shall not wear a woman's garment. And if so, these matters are divided by lands and times. Every time and every place that it is the manner of women to do thus, men are prohibited there. And every place where it is the manner of both men and women, it is permissible. For it isn't exclusive to women in that place or time, and I don’t call it a woman's garment. And this matter is not clear in my eyes, because of that young Torah scholar (Nazir 59a):…The entire people except for the [pious] individuals would remove their armpit hair, and even so, Torah scholars [exemplified by a young scholar] had the custom to treat it as a prohibition. And for what reason? For behold, it was not a woman's garment in their generation, and hadn't it returned to being a man's garment? Rather, any matter that is fitting for women and not for men, and the women do thus, it is prohibited to men because of "a woman's garment." And one who has become accustomed to a prohibited matter, and is drawn into it, and the masses are drawn into it, the prohibition does not become permissible. For if so, a person would persist in sinning, and [pious] individuals are more careful with this.
This responsum does not tell us explicitly how Rashba regards a change in norms initiated by non-Jews, though it strongly implies that he'd meet it with reservations. The responsum does reveal Rashba's discomfort with a related question that likewise results from simlat isha's contingency with respect to place and time. A halachically observant Jew may not initiate the adoption of dress and grooming norms associated with a different gender. And yet, a once-transgressive change can eventually lead to a shift in how halacha categorizes a given accoutrement. Rashba rules that the masses can follow the changed definition, but the pious should not adopt change where it began in sin.
We have seen that the Ge'onim take non-Jewish practice into account in determining local custom, and Rashba might as well, with some reservations. In his comments on Tur, Derisha presents two perspectives on the question of who establishes custom: non-Jews as well as Jews, or Jews alone:
Perisha 182:5
It seems that he [Tur] wanted to say that non-Jewish men, since it has become practiced, it has become practiced, and we learn from the custom of non-Jews. One can also [alternatively] say that he [Tur] was speaking of Israelites, for where all of them together have taken on the practice, we do not protest them.
On his reading, when Jews as a whole take on a norm of dress, it becomes accepted. He does not mention stringency for the pious as Rashba suggested.
In practice, especially when Jews interact with surrounding culture, it is very difficult to isolate the Jewish community from broader trends in clothing. In a parallel discussion of the prohibition of adopting chukat ha-akum, the ordinances of idolators, and its implications for modern dress, Rav Moshe Feinstein acknowledges that changes in dress typically transcend religious boundaries:
Responsa Iggerot Moshe YD I 81
The prohibition of dressing in the clothes of non-Jews does not apply [to modern-day Western dress] for almost all Jews wear these clothes. And if so, who says they are the clothes of non-Jews and Jews are wearing their clothes? And why should we not say that from the outset [they are] also clothes of Jews, for they were not designated at all from the beginning for the non-Jews and afterwards also for Jews, for from the beginning they were also made for Jews…
In the mid to late twentieth century, halachic discussions arose about whether women’s pants violated the prohibition of keli gever. Some authorities, including Rav Yitzchak Weiss, maintained that trousers are always intrinsically considered a keli gever, even where women's trousers are common.
Responsa Minchat Yitzchak II 108
Really they [women’s trousers] are fully keli gever, for they are still called “trousers,” even though they are a little different…
Others, however, argue that since definitions of keli gever vary with place and time, and since women’s pants, or gender-neutral ones, have become ubiquitous, a woman wearing trousers does not violate the prohibition of keli gever. (We discuss potential tzeniut concerns with a woman wearing trousers here.)
Responsa Yabia Omer VI YD 14
Since the matter of women wearing trousers has spread nowadays to many places, there is no issue of keli gever, since in any case it is not designated specifically for men. Even more so since there is a recognizable distinction between women’s and men’s trousers.
Although Jews have some specific standards of tzeniut in dress, norms for gendered dress in surrounding society would seem to remain relevant to us.
Does Halacha always consider gender to be binary?
Modern scientific and psychological literature offers a range of definitions for sex and gender, from the genetic to the cultural, and has increasingly brought to the fore those who do not fit neatly into the categories of male or female.
For its part, the Torah presents gender as a foundational category established by God, beginning with Bereishit, when God creates male and female, who perhaps begin linked, but are split off from each other. (See more here.) In a number of places, the Torah also distinguishes man from woman with respect to its laws. The Torah does not explicitly recognize other gender categories.
Halachic literature defines gender based on sexual anatomy (genitalia), and this leaves some gray area within halachic discussions of gender. Working with anatomical definitions, Halacha recognizes intermediate or intersex categories, tumtum and androgynos: the tumtum is someone whose genitalia are undifferentiated, and the androgynos has both male and female sexual organs. 
How does Halacha relate to a tumtum or an androgynos with respect to dress? The Tosefta, followed by Rema, instructs them not to wrap their heads like women:[2]
Tosefta Bikkurim (Lieberman) 2:3-4
An androgynos has some ways that are equivalent to men, and has some ways that are equivalent to women, and has some ways that are equivalent to men and women, and has some ways that are equivalent to neither men nor women. Ways that are equivalent to men:… he does not wrap [his head, as women do] and cuts his hair [rather than growing it long], like men…
Rema YD 182:5
A tumtum and androgynos are prohibited to wrap [their heads] like a woman [does].
Note that the halacha for a tumtum or an androgynos not to wrap like a woman, or perhaps to dress more like a man overall, does not obligate them to take on a clearly defined gender. As the Tosefta notes, a tumtum or an androgynos occupies an in-between gender space, in some ways like men, in some ways like women, in some ways like both, and in some ways like neither.
The very existence of a halachic middle ground, reflects a picture of gender within Halacha that is more complex than it might first appear. With respect to keli gever, Halacha recognizes that definitions of what makes an item a man's or a woman's are contingent on culture, and treats intent as a major element in defining the prohibition.
Still, a view of gender as rooted in Divine will and defined by anatomy means that the primary discourse on keli gever focuses on those who fit into a gender binary. While transgender issues require their own, extensive treatment and thus lie beyond the scope of this piece, we recognize that they remain acute for many, and that discussion of keli gever in this context can be especially sensitive.
Gender-Neutral Clothing
The verse of prohibition in the Torah refers specifically to a woman with a male article and a man with a woman's garment, and halachic discussion follows suit. This would seem to leave room for a man or woman to wear gender-neutral items of clothing.
We find an example of a man and woman wearing the same garment (at different times) in the Talmud:
Nedarim 49b
The wife of Rabbi Yehuda went out, she took wool and made an embroidered cloak, when she went out to the market she'd cover herself with it, and when Rabbi Yehuda went out to pray, he'd cover himself with it and pray…
The continuation of the passage implies that Rabbi Yehuda and his wife share a cloak because they are too poor to afford two of them. Maharsha here writes that this was permissible because gender-neutral garments, such as cloaks, do not fall under the prohibition:
Maharsha Chiddushei Aggadot Nedarim 49b
It seems to me that this cloak was made like a sort of outer robe and it teaches is that even though his wife went out in it to the marketplace, it does not entail a prohibition of "a man shall not wear a woman's garment," which is specifically a garment made specially for a woman, but the garment of a jacket is special to both of them [genders]. With respect to women it is said "for so the daughters of kings wore jackets" and regarding a male you will find many [mentions] in Scripture and it doesn’t entail "a man shall not wear."
Elsewhere, the Talmud implies that it might sometimes be difficult to distinguish between a husband's and wife's clothing without adequate lighting. Tosafot explain that men's and women's clothing at that time were largely equivalent:
Tosafot Shabbat 12a
Even to distinguish between his garment and his wife's garments—Their way was for them to be equivalent.
This implies that gender-neutral clothing is permissible, though Rav Wosner reports that Rav Ya'akov Emden called for some differentiation until puberty, to make it clear whether a child is a girl or a boy.
Responsa Shevet ha-Levi 9:175
Ya'avetz in his glosses to Shabbat 12a proved from the Tosafot there that even when they are equivalent there is no prohibition of "a man shall not wear" and he proved it from Nedarim 49b, but he wrote that in any case certainly there must be another recognizable [marker of gender] to distinguish between male and female when they are children, at least until he grows a beard for a male and until breasts develop for a female.
Rav Emden apparently was concerned that there be a visible distinction between genders. Nevertheless, he did not view gender-neutral clothing as subject to prohibition, since gender can be made clear in other ways.
What of a woman wearing a sweater sold in the men's section of a store, that is not shaped with a special men's fit? Or borrowing a gender-neutral garment previously worn by a male? Maharikash rules that when the shape of a given item of clothing shows no sign of being intended for a specific gender, it is permissible for anyone to wear it:[3]
Ohalei Ya'akov Maharikash 71
When we look closely at the words of the halachic authorities, one knows clearly that a woman is only prohibited in an item where the form of that garment is exclusive for men, and a man is only prohibited in an item where the form of that garment is exclusive to women. But a garment whose form is the same for men and women is permitted to all, and we are not at all concerned about for whom it was made …And this is the language of Rambam…He said "a woman should not adorn herself in men's adornments and a man should not adorn himself in women's adornments" and to imply that we follow whose it is. He also made the matter contingent on the region, which implies that we are not concerned for whom the item was made, and it is permitted to a man and to a woman even if it was made for one of them…
Taken more broadly, the permission to wear gender-neutral clothing establishes that keli gever does not obligate a woman to seek out distinctly feminine clothing, where "feminine" is subject to shifting definitions, but only prohibits her from wearing clothing considered specifically "masculine."
Must women's clothing always be feminine?
The world of fashion has often flirted with gender-neutral or unisex clothing, even billing London Fashion Week in 2021 as gender-neutral. Fashion can work in opposing directions, sometimes challenging gender conventions and sometimes exaggerating them. But the avant garde is by definition not common custom, and defining gender-neutral clothing in actual practice can be as slippery as defining gendered clothing.
Even if they began as part of the avant garde, social changes typically do find expression in dress. In the wake of feminism, as women have entered formerly male-dominated spheres, women have adopted items of clothing formerly associated with men (e.g., baseball caps or sports jerseys). This is often the case even within the religiously-observant community, tzeniut considerations aside, so that the number of clothing items clearly considered to be keli gever has dwindled.
Men's roles have undergone less of a shift. While some forms of grooming and some types of jewelry have become more common for men of late, the bounds of what is typically worn by men remain more circumscribed.
Halacha acknowledges that many gendered items of clothing are subject to changing contextual definitions, and does not obligate us to emphasize their gendered aspects. A woman seeking to dress like a woman need not dress in pinks and florals—unless they speak to her. A woman wearing a skirt out of respect for tzeniut or communal norms need not wear one considered overtly feminine, and might otherwise dress in a gender-neutral fashion, since Halacha permits the wearing of gender-neutral clothing.
The prohibition of keli gever recognizes and reinforces a society's gender distinctions for appearance. It does not tell us what our personal conception of gender must be and leaves room for a range of self-presentation in women's attire, from the conventionally feminine to the more gender-neutral.
The Prohibition
Now that we've seen halachic discussion of what type of article constitutes a keli gever, it's time to discuss the nature of the prohibition. Let's begin by looking more closely at the wording of the verse.
Devarim 22:5
A man’s article shall not be on a woman, neither shall a man wear a woman’s garment; for whoever does these things, it is an abomination to the Lord your God.
The prohibition of keli gever employs the broader verb "to be" rather than the verb "to wear" and the general word "keli," article, rather than a more specific word (such as beged, garment). This broad phrasing implies that "keli gever" refers to more than just clothing. In this vein, Targum Yerushalmi writes that other types of articles that can be put on, such as tzitzit and tefillin, fit under the prohibition of keli gever.
Targum Yerushalmi Devarim 22:5
There shall not be a cloak of tzitzit and tefillin, which are men’s articles, on a woman.
We discuss this view of tzitzit and tefillin here and here.
Targum Onkelos indicates that keli gever refers to a woman not having a weapon upon her. He goes on to translate simlat isha to refer to men adorning themselves in the manner of women:
Onkelos Devarim 22:5
A man's adorning weapon shall not be upon a woman, and a man shall not adorn himself with a woman's adornments…
Tannaitic Views
In a midrash halacha with parallel versions in Sifri and in the Talmud, Rabbi Eliezer ben Ya'akov picks up on Targum Onkelos's definition:
Sifri Devarim 226:5
Rabbi Eliezer ben Ya'akov says: Whence do we know that a woman should not wear a weapon and go out to war? The verse teaches "a man's article shall not be upon a woman." And [that] the man should not decorate himself with women's ornaments? The verse teaches "and neither shall a man wear a woman's garment."
Echoing the Targum, Rabbi Eliezer ben Ya'akov teaches that a woman may not wear a weapon for war, typically associated with men,[4] and that a man may not adorn himself in the manner of women. As we saw above, Rambam views armor as a paradigmatic example of a keli gever. (We discuss women wielding weapons for self-defense later on, and women waging war here.) This view is also taken to prohibit men from performing certain acts of grooming associated with women, such as removing body hair.[5]
Rabbi Eliezer ben Ya'akov's ruling suggests that a single, male-associated article, such as a weapon, could lead to a violation of keli gever, even if a woman's overall appearance otherwise remains consistent with other women's. He also seems to extend the prohibition to behavior strongly associated with another gender, as opposed to restricting it to dress.
In both the Sifri and the Talmud (below), Rabbi Eliezer's viewpoint is preceded by a first, unattributed view, referred to as Tanna Kama.[6] It's unclear to what extent the two opinions agree or disagree.
Nazir 59a
As we learn [in a Baraita]: "A man's article shall not be upon a woman," what does it come to teach us? If it were that a man should not wear a woman's garment and a woman a man's garment, behold, it is already said "It is an abomination," and there is no abomination here. Rather, that a man should not wear a woman's garment and sit [alt. dwell] among the women, or a woman a man's garment and sit [alt. dwell] among the men. Rabbi Eliezer ben Ya'akov says: Whence do we know that a woman should not go out [garbed] in weapons for war? The verse teaches "a man's article shall not be upon a woman and neither shall a man wear a woman's garment" – that a man not adorn himself with women's adornments…
Tanna Kama infers that wearing a garment associated with another gender is not prohibited unless the cross-dressing would lead to an "abomination." He defines this as cross-dressing that facilitates a man sitting, or dwelling, among women, and vice versa, but does not state explicitly why this would be of concern.
According to Tanna Kama's view, it is possible that violating the prohibition would depend on dressing to appear like a member of another gender, and perhaps even to dwell among them. If so, wearing a single, male-associated article or garment would not violate the prohibition of keli gever so long as a woman's general appearance would otherwise remain consistent with women's dress.[7]
Ruling Like Rabbi Eliezer ben Ya'akov
Rambam rules in accordance with Rabbi Eliezer ben Ya'akov, as do a number of halachic authorities.[8] He reads Rabbi Eliezer's use of "weapon" as an example of any signature male article of adornment, not as a reference to going out to war,[9] and rules that a woman wearing even one such item violates keli gever:[10]
Rambam, Laws of Avoda Zara 12:10
A woman should not adorn herself in men's adornments, such as putting a turban or a hat on her head, or wearing armor and the like.
Beit Yosef explains that Rabbi Eliezer ben Yaakov views the prohibition for a person of one gender dressing to appear like another as taking effect even from the first article put on, as long as it is visible:
Beit Yosef YD 182
…Nevertheless these words regard switching one of the discernible items that distinguish between a woman and a man…For even if she did not change a thing out of all of her clothing but she placed a weapon upon herself, and so too a man even if he did not change a thing but adorned himself with a woman's adornment, it is prohibited because these are among the things that lead to abomination as I have explained. And how much more so where they switched their garments [in full], which leads more to an abomination, that it is prohibited, even if he does not sit among the women.
Rema follows Beit Yosef's view prohibiting the wearing of even a single discernible item associated with another gender:
Rema YD 182:5
Gloss: And even with one item of clothing it is prohibited, even though it is discernible from the rest of their clothing that it is a man or a woman.
Let's delve further into the rationale behind the prohibition of a woman having a keli gever upon her, and the circumstances under which it applies.
Now that we've explored the definition of keli gever, we should consider why it should be prohibited to women. By using the word "abomination," the Torah itself opens up a discussion of what purpose the prohibition serves.
Although early halachic authorities certainly treat gender as an important principle of categorization, they do not typically present blurring gender lines per se as the definition of "abomination." Ibn Ezra does hint at something like this in a philosophical work:[11]
Ibn Ezra, Sefer Yesod Mora 9
"A man's article should not be and neither shall a man wear…" [These are] the opposite of God's work…
Ibn Ezra suggests that gender is a God-given element of our nature, and that the blurring of gender boundaries runs counter to the work of Creation. However, this approach is largely absent from the halachic discussion, in which we find three other explanations of the nature of the concern:
I. Following Idolatrous Practice  Rambam writes that the prohibitions stem from associations of cross-dressing with idolatry. He describes the phenomenon in his Guide to the Perplexed:
Rambam, Guide to the Perplexed, Friedlander trans, 3:37
The woman shall not wear that which pertains unto a man" (Deut. 22:5). You find it in the [idolator's] book Tomtom, that a male person should wear colored woman's dress when he stands before Venus, and a female, when standing before Mars, should wear a buckler and other armor.
As we saw above, Rambam places his discussion of keli gever in Mishneh Torah in the section devoted to idolatry. This suggests that Rambam views connections with idolatrous practice as the driving force behind the prohibitions.
II. Arousal to Licentiousness Rambam suggests an additional reason for the prohibition, that cross-dressing can foster arousal, perhaps because the clothing is associated with a gender that one finds sexually attractive.[12]
Sefer Ha-mitzvot of Rambam, Negative Commandment 40
Know that this action, that is to say women being adorned with men's adornments or men with women's adornments, is sometimes done to arouse the nature to licentiousness as is well known among those who are promiscuous, and sometimes it is done for heretics as idolatrous service…
Now, Tanna Kama (above) states clearly that simply wearing clothing associated with another gender does not fall under the Torah's prohibition because it is not on its own an "abomination." Rambam's suggested rationale, that the act of cross-dressing in itself is potentially arousing, might thus not be consistent with Tanna Kama.
It is possible that Rabbi Eliezer ben Ya'akov prohibits donning even a single cross-gender adornment as an arousing act in itself. However, Beit Yosef argues that Rabbi Eliezer ben Ya'akov agrees that "abomination" here does not refer to cross-dressing being arousing in itself:
Beit Yosef YD 182
…For Tanna Kama raised the difficulty "And is it not already said that it is an abomination and there is no abomination here." For one cannot say that [Rabbi Eliezer ben Ya'akov] does not consider this a difficulty because he thinks that a man wearing a woman's garment or the opposite is an abomination in itself, for if that were so, why would he specify weaponry and women's adornments…
Beit Yosef supports this claim by pointing out that Rabbi Eliezer specifies weapons or adornments as abomination, rather than mention clothing in general, and therefore seems to be defining the prohibition more narrowly than Tanna Kama.
III. Dressing to Resemble, Leading to Licentiousness  Tanna Kama states that cross-dressing in order to enter a space reserved for another gender would be an abomination, an assertion with which Rabbi Eliezer ben Ya'akov might agree. Why, exactly, would this be problematic?
In his Torah commentary, Rashi assumes that cross-dressing to make oneself appear like a member of another gender would facilitate mixing and licentiousness:
Rashi Devarim 22:5
A man's article shall not be upon a woman - That she resemble a man in order to go amongst the men, for this is only for the sake of illicit sexual behavior. And a man shall not wear a woman's garment - to go and sit among the women…For it is an abomination - The Torah only prohibited clothing that leads to an abomination…
The concern is that a woman might fully disguise herself as a man to gain access to male-only spaces in order to engage in licentious behavior. Furthermore, as we've seen elsewhere, there are halachic concerns regarding men and women mixing socially. Cross-dressing elevates these concerns because it could lead to a more extreme or constant level of mixing, assumed to be of licentious purpose. Sefer Ha-chinuch explains:
Sefer Ha-chinuch 542
…Among the roots of the mitzva is to distance from our sacred people matters of immodesty and every matter and aspect in which a stumbling block in that matter will be found, like that which they [our sages] would say by way of a parable that God hates licentiousness, which is to say that out of love for us He distanced us from licentiousness, which is an exceedingly ugly matter and takes a man's heart and sways him from the good way and desirable thought to a bad way and thought of folly. And there is no doubt that if the clothing of men and women were to be equivalent, they would mix with each other constantly and the land would be full of licentiousness. And they further said regarding the rationale of this mitzva that it is to distance any matter of avoda zara, for thus was the way of those who serve idols.
For Sefer Ha-chinuch, as for Rashi, retaining distinctive dress for men and women chiefly serves to prevent licentiousness.
Netziv argues that adorning oneself or bearing a weapon reflects something fundamentally female or male in nature. Ultimately, though, his concern with a woman learning to bear a weapon is not that she masculinizes herself per se, but that doing so will help her resemble a man and mingle with men:
Netziv, Ha'amek Davar, Devarim 22:5
The verse warns about… changing nature, that a male article, i.e., a weapon, which in the nature of a woman she should not gird herself with a sword, if she does not train herself in it for some stretch of days, and if so it is a preparation so that later she can change her clothing and go among the men, and naturally so too is the opposite, that a man is warned not to become accustomed to the nature of women to beautify themselves and the like, in order that he easily be able to change into women's clothing.
If the prohibition of keli gever is closely tied to a given rationale, then perhaps some instances of a woman donning male articles would not fall under the prohibition, depending on her intent.
Of the three main explanations for is the prohibition, concern for dressing to appear like another gender in a way that could lead to licentiousness becomes most central to halachic discourse. Focusing on this rationale, halachic authorities define the relationship of intent to the prohibition in a few ways:
I. Prohibited only with Licentious Intent  Sefer Mitzvot Katan (Semak) asserts that the Torah-level prohibition of lo yilbash applies specifically to one who cross-dresses in order to have illicit relations:
Semak 33
That a man not wear a woman's garment, as it is said, a man should not wear a woman's garment. The explanation is in order to have illicit sexual relations.
Meiri writes similarly:
Meiri Nazir 58b
The general rule is that this [person] should not make use of the thing that is customary for this [person of another gender] in a plotting way and as preparation for illicit sexual relations.
It follows from these views that cross-dressing without licentious intent would be permissible on a Torah level.
II. Generally Prohibited Regardless of Intent  On the opposite end of the halachic spectrum, Yere'im seems to maintain that keli gever is prohibited irrespective of a wearer's intent. So, for example, even a woman performatively donning keli gever for a very brief period of time would violate the prohibition:
Yere'im 386
…A man should be careful not to adorn himself with women's adornments. And it is all according to local custom, with the adornments and clothing with which the local women are accustomed to adorn themselves, and for their clothing to be distinct from men's clothing. He should be careful with all of them so as not to adorn himself. And a woman with men's clothing when there is no equivalent in women's dress…And it is prohibited to wear it even on an occasional basis and for fun, for the verse did not distinguish between a fixed [act] and an occasional one, and since I saw men dressing in women's clothing temporarily for fun [Bach's version of the text includes: And also a woman in men's clothing on an occasional basis, at parties for a groom and bride] and the matter was difficult in my eyes, I wrote it here.
Even Yere'im would likely make an exception, however, for the sake of self-defense. Midrash Tannaim on Devarim derives from the verse that donning keli gever is permissible in the face of peril, when there is no abomination:
Midrash Tannaim Devarim 22:5
Or [one might think] he [should not] do this out of concern for [threatening] non-Jews and for bandits? The verse teaches us " for whoever does these things, it is an abomination to the Lord your God."
So, too, Sefer Chassidim permits a woman to disguise herself as a man and to bear arms in order to elude danger:
Sefer Chassidim (Margoliyot) 200
It is a time for act to God, they have violated your Torah (Tehillim 119:126). Even though the Torah said "a man's article shall not be on a woman, neither shall a man wear a woman’s garment," if enemies capture a city or if they are traveling on the way and if they [the enemy] were to know that they are women they would rape them, [then] they [the women] should go in men's clothing and even with a sword in order that they [the enemy] think that they are men. And if there are only ten men and there are some women, they should gird themselves with a sword so that they [the enemy] will think that they are men and not harm them.
Presenting danger as unique grounds for permission strongly implies that intent does not otherwise affect the prohibition. Later authority Yad Ha-ketana writes explicitly that intent for other purposes is irrelevant once a woman intentionally puts on keli gever:[13]
Yad Ketana Avoda Zara, Lo Ta'aseh 31, Minchat Ani 82
…Do Torah prohibitions depend on one specifically intending to violate the prohibition? The matter depends on intending to perform the [prohibited] act.
III. Prohibited Unless for Functional Purpose  In an attempt to clarify when a man's looking in the mirror would be considered a prohibited act of feminine grooming, Tosafot draw a distinction based on intent:
Tosafot Avoda Zara 29a, s.v. one who has his hair cut
…It sounds as though the fact that it is prohibited on a weekday [for a man] to look in the mirror…is only prohibited when it is to beautify himself, that he transgresses "lo yilbash" but in order to cut his hair and to shave and to look in the mirror that he not injure himself, or [to treat] an eye malady, it is certainly permitted and He who examines the heart, He knows [the intention]…
According to Tosafot, a prohibition only applies when the man acts to beautify himself, but not when he looks in the mirror to guide haircutting or medical care. Their analysis opens the door for other distinctions based on intent.
Rambam (above) describes the prohibition as "women adorning themselves with men's adornments." Perhaps he hints at something similar, that putting on a male-associated article for a purpose other than adornment, or one that is not considered an adornment, would be permissible.
Along these lines, Bach rules that the prohibition of keli gever applies to cases in which a woman seeks to adorn herself to resemble a man, and not when a less decorative and more functional article of clothing is worn for a constructive purpose such as protection from the elements.
Bayit Chadash YD 182
…It may be permitted in two ways. One is that there is no prohibition even of an item that is for beautification and decoration unless the woman wears men’s clothing to resemble a man…but if they wear [it] in order to protect against the sun in the sunny season and rain in the rainy season, there is no prohibition in that case…The second, that even to resemble [men] is prohibited only for items that are made for beautification and decoration…And thus wrote Rambam, "A woman should not adorn herself in male adornments”…But Rav Eliezer of Metz in Yere'im 96 (385/6)…implies that it is prohibited for all clothing that is distinct between man and woman – and this is certainly impossible…Rather, the Rav [Yereim] relied on that which he wrote at first [absent from our versions of Yere'im], that [specifically] matters that are adornments and beautification and beauty for the woman, such as removing hair from the underarm and pubic area, that is what is prohibited, and about this he said: “therefore a man should be careful that he not groom himself with feminine grooming…”
Bach, who had a different version of Yere'im, even claims that Yere'im meant to allow for cross-dressing for functional purposes.
Unconvinced by Bach, Shach limits application of Bach's argument to situations in which the woman's overall appearance otherwise remains like that of other women. To Shach, if a woman's dress is fully like that of a man, intent is no longer grounds for leniency.
Shach YD 182:7
She should not adorn herself…And his [Bach's] words are not necessarily correct, and in any case it seems that is specifically regarding a woman's adornments. But if a man really wears a woman's clothing until it is unrecognizable that he is a man, and vice versa, it is prohibited in any case [regardless of intent]. And so wrote Rav Eliezer of Metz in Yere'im…
Earlier, we discussed the view that even one item could constitute a violation of keli gever. Shach adds that a permission based on intent goes beyond one item, but still has a limit. When a woman wears a keli gever for functional reasons, there needs to be at least some outward sign of her gender.
For a Mitzva or Joy
The version of Yere'im recorded by Bach rejects customs for cross-dressing as part of wedding festivities.[14] Since adding to the bride's rejoicing is considered a great mitzva, this wording would clearly indicate that intent to fulfill a mitzva does not set aside concerns for keli gever.
At the same time, we find that other early halachic authorities reached the opposite conclusion with respect to costumes on Purim. In some communities, a custom developed for men and women to dress as each other on Purim. While Rambam would likely reject this custom, Mahari Mintz justifies it for the sake of adding to Purim rejoicing.
Responsa Mahari Mintz 15
On the matter of wearing costumes that young men and also young women, the elderly and the youth, are accustomed to on Purim. I saw that Rav Elyakim Segal, my beloved colleague, already ruled to permit it and published his ruling with its reasoning and his proofs establish its soundness…and if there were, Heaven forfend, a drop of transgression, Heaven forfend that they [the rabbis who permit it] would be quiet and not protest, and how much more so regarding a prohibition [from the Torah]; rather, it is certain that they had a proof and grounds to rely on that it is totally permissible…And it seems to me a proof in the matter [from the Tosafot]…it is only prohibited when it is to beautify himself, that he transgresses "he shall not wear"; but in order to cut his hair and to shave and to look in the mirror that he not injure himself, or [to treat] an eye malady, it is certainly permitted, and "He who evaluates the heart, He is the one who knows [the intention]"…And since Tosafot hang it on…"He who evaluates the heart is the One who knows," and that it is only prohibited for beautifying himself…therefore in another fashion it is permissible…For Semag also thought that one only violates "he should not wear" when his intention is for illicit sexual activity…Further is found in a responsum written by Rabbeinu Tuvya in the name of Riva that  any food that the young men snatch…at the time because of the joy of Purim is not called theft since he does not do it to steal and profit but rather out of Purim rejoicing; here too, our case is no different. Since he does not intend for sexual misconduct but rather for the joy of Purim…
Once the prohibition is understood to depend on intent, Mahari Mintz sees intent for Purim rejoicing as sufficient to permit keli gever, especially because people of his day were also lenient about mock-theft on Purim.
Perhaps surprisingly, Bach, who applies leniencies based on intent widely, rejects this argument.
Bach YD 182:5
One should take notice of what they are accustomed to do on Purim, to change clothes from man to woman and from woman to man, and no one protests. And according to what I wrote regarding things done for beauty and adornment, it is prohibited according to all to intend to resemble [another gender]. And Mahari Mintz already responded on this as explained in his responsum, and he said that since he only does this out of rejoicing for Purim, it is not prohibited…And it seems in my humble opinion that his words regarding this are refuted from what Yere'im wrote explicitly, that even in parties for a groom and bride there is a prohibition; therefore, even what he does out of rejoicing for a mitzva is not similar to doing it in order to spare himself discomfort, and so it is logically, for to spare himself discomfort cannot be done in another way, but for rejoicing of a groom and bride and rejoicing on Purim, many types of rejoicing are possible without transgressing the prohibition of "he should not wear." And there is no doubt that were the words of Yere'im not hidden from Mahari Mintz, he would not have written so.
Bach allows for considerations of intent to determine the halacha when there is a clear functional purpose for the wearing of keli gever, aside from dressing up; as above, he sees this view as consistent with Yere'im. He does not view simchat Purim as sufficient grounds to permit cross-dressing for beautification or to resemble another gender, a position ruled out by his version of Yere'im.
In practice, Rema provides support for the custom for leniency regarding costumes on Purim:
Rema OC  696:8
Gloss…And that which they were accustomed to do, to wear costumes on Purim, and a man would wear a woman's garment and a woman a male article, there is no prohibition in the matter since they only intend simply for rejoicing…And there are those who say that it is prohibited, but the custom is in accordance with the first rationale. And similarly, people who snatch from each other by way of rejoicing, this does not entail "don’t steal"…
Others, including Peri Megadim, are less embracing of this view. Like Shach, they restrict leniency to when the dressing up is limited and the person's gender is clearly discernible:
Peri Megadim OC Mishbetzot Zahav 696:5
It appears that when all the garments are a man's, and only one garment is of a woman, and they are discernible, also according to many opinions in Yoreh De'a 182, there is no Torah prohibition in this case, and one should not protest on Purim.
Nevertheless, Rema establishes a practical precedent for intent overriding concerns for keli gever. More recently, in considering a woman laying tefillin, Seridei Eish writes that intent to fulfill a mitzva would in fact override concerns about keli gever:
Responsa Seridei Eish II 41:13
From the text of Eiruvin 96a: Michal the daughter of Shaul laid tefillin and the sages did not protest her. And this is difficult, why did they not protest her? Behold, it is prohibited to wear tefillin because of " a man’s article shall not be on a woman "; according to Targum Yonatan ben Uzziel, "There should not be fringes of tzitzit and tefillin, for these are male articles, on a woman." It must be that since she intends for the sake of a mitzva, there is no prohibition of 'do not wear' here.
A look back at Rema, however, reveals that he refers not specifically to a mitzva but to "simcha be'alma," mere rejoicing. Thus, some have argued that dressing up in the context of a play or other dramatic purpose is subject to the same parameters as dressing up on Purim.[15]
Indeed, a common convention in theater in some halachically-observant circles is for all-female or all-male productions to allow for cross-dressing only in a limited way, for example leaving a skirt on a woman otherwise dressed like a man, so that the actor's sex remains clear. This approach resembles Peri Megadim's recommendation for Purim and Shach's in general.
For Self Defense
As we saw earlier, Rabbi Eliezer ben Ya'akov prohibits a woman to "wear weapons and go out to war." What about for self-defense? This question plays an important role in evaluating the permissibility of army service for women.
A midrash teaches that Yael used a tent peg to smite Sisera because using a sword would have violated keli gever.
Midrash Mishlei Parasha 31
Yael: for she didn't kill Sisera with a weapon, rather with a tent peg and her strength of hand. And why did she not kill him with a weapon? In order to fulfill what is said that a keli gever not be upon a woman.
Still, we saw that Midrash Tannaim and Sefer Chassidim allow for keli gever in a case of danger. The logic seems to be that Yael would have been permitted to use a sword were a tent peg not at hand.
Many recent authorities, including Rav Moshe Feinstein and Rav Ovadya Yosef, have affirmed that a woman may bear arms as necessary for self defense:[16]
Responsa Yechaveh Da'at 5:55
In our case, where the intention of the teachers in bearing arms is not to resemble men, but rather to defend their lives and the lives of their students under their charge and supervision, it appears that the matter is clear that it does not entail violation of "there should not be keli gever on a woman"…It is permissible for the teachers and nursery school teachers in the border settlements to train and to carry weapons at their times of watching over the schools, as long as they are very careful regarding the rules of tzeniut when they train, as is suitable for proper daughters of Israel…
When not for self-defense, many authorities, including Seridei Eish, view a woman bearing arms as prohibited on a Torah level, without conditioning the prohibition on a woman "going out to war:"
Responsa Seridei Eish II:41:32
…Rather Rambam, and along with him all the early halachic authorities, did not explain it thus, and think that it is not specifically going out to war, but rather ornamentation in men's clothing in general is prohibited. And in any case for those early authorities who think that Rabbi Eliezer ben Ya'akov prohibited wearing clothing exclusive to men on a Torah level, military weaponry is prohibited to women on a Torah level, even If they do not go out to war, if they only wear army uniforms it is prohibited.
If Rabbi Eliezer ben Ya'akov's concern is wearing a weapon, as a classic example of a male adornment, then one might argue that this, like other aspects of keli gever, depends on time and place. In that case, perhaps it would no longer be prohibited in Israel, where women in the IDF routinely carry weapons. Rav Yehuda Henkin suggested this as a possible justification for religious women bearing weapons in the army.
Rav Yehuda H. Henkin, "Bearing Weapons by Women and their Service in the Army," Techumin 28, p. 271-3
…For the rifles are no longer in the category of an article exclusive to men…In the Land of Israel today, thousands of girls are drafted or volunteer to serve in the army…It is impossible to say that they are in a country where the M-16 rifle is exclusive to men. And it makes no difference if most women in the IDF aren't religiously observant, for even if they were all non-Jews; in any case, their practice establishes the matter of [defining] a man's or woman's garment…Therefore, one should not consider female soldiers to be violating a Torah-level prohibition of a man's garment, at any rate after the fact…In Sifri Devarim, the language is "Whence that a woman not wear a weapon and go to war"…According to this, the prohibition is regarding wearing, and it seems correct to explain the Baraita [the parallel Talmudic passage] thus, and so is the meaning of the verse…and this is the source of Rambam’s close reading…We did not find in his works that Rambam mentions a prohibition of bearing a weapon, as distinct from clothing…we have taught favorably about women who bear or take weapons in the [Israeli] army.
Concluding Thoughts
The prohibition of keli gever may raise more questions about gender norms than it answers. Dr. Erica Brown alludes to what clothing can do and what it can't:[17]
Dr Erica Brown, Dress for Success, Jewish World Review, 12.16.16
In Hebrew the word for clothing "beged" is the same root as the word for traitor "boged." Clothing conceals and reveals, and therefore it involves a lot of decisions about how we present ourselves to the world.
As we've seen throughout this series, our choices about dress are consequential, and our self-presentation can be religiously and socially revealing. The halachot of keli gever are part of this broader picture, pushing us to be sensitive to gender norms when we dress, while making it clear that these norms are complex.
Further Reading
"Lo Yilbash," Olamot Shiur, available here: https://olamot.net/shiur/%D7%9C%D7%90-%D7%99%D7%9C%D7%91%D7%A9-0
Ellinson, Rabbi Elyakim Getsel. Woman and the Mitzvot: Guide to the Rabbinic Sources Vol. 2, The Modest Way, trans. Raphael Blumberg. Jerusalem: World Zionist Organization Department for Torah Education and Culture in the Diaspora, 1992.
Haber, Rav Shemuel. Et Tzenu’im Chochma, Vol. 1. Karnei Shomron, 2007.

[1] Nazir 59a
This man who was liable for [rabbinic] lashes before Rabbi Ami, [when] his armpit was uncovered, he [Rabbi Ami] saw that he did not shave. Rabbi Ami said to them: Leave him, this [man] is from our fellows [who are scrupulous in mitzvot].
[2] The text of the mishna here parallels the Tosefta:
Mishna Bikkurim 4:2
How is [an androgynos] equivalent to men?...He wraps himself and cuts his hair like men; marries [a woman] but is not married [to a man], like men; and is obligated in all of the mitzvot said in the Torah, like men.
[4] Elsewhere, the Talmud tells us that men wage war, and this is not typical of women.
Kiddushin 2b
For the way of a man is to make a war, and it is not the way of a woman to make war.
[5] Sefer Ha-chinuch Mitzva 543
The laws of this mitzva are what our sages said [Makkot 20b], that the prohibition and lashes are not only for clothing, for thus is the law for their adorning, for whoever adorns himself with grooming practices exclusive to women is liable for lashes, such as one who plucks out white hairs from among black hairs from his head or from his beard, and so one who dyes his hair in the way that women dye it, and so translated Onkelos: a man should not adorn himself with adornments [grooming] of a woman.
Shulchan Aruch YD 182:6
To pluck out even one white hair from among black ones [is prohibited] on account of "a man should not wear"…
Shulchan Aruch YD 156:2
It is prohibited for a man to look in the mirror. Gloss: There are those who say specifically in a place where it is only the way of women to look in the mirror…
[6] This is the full text of the Sifri:
Sifri Devarim 226:5
"A man's article shall not be upon a woman" What does it come to teach us? That a woman should not wear white articles and a man should not cover himself with colored ones? The verse teaches "It is an abomination," a matter that leads to an abomination. This is the rule, that a woman should not dress like a man and go among the men, and a man should not adorn himself with women's decorations and go among the women. Rabbi Eliezer ben Ya'akov says: Whence do we know that a woman should not wear a weapon and go out to war? The verse teaches "a man's article shall not be upon a woman." And [that] the man should not decorate himself with women's ornaments? The verse teaches "and neither shall a man wear a woman's garment."
[7] Responsa Seridei Eish II 41:7
…For even though in general we don’t expound the rationales of verses, in any case here the Torah explicitly revealed the rationale, as it wrote it "for it is an abomination to the Lord your God whoever does these"…And even though in the verse the condition that he sit amongst the women is not stated, in any case, since the verse calls it an abomination, we can only prohibit what is an abomination, but not what isn't an abomination.
[8] Gittin 67a
The teaching of Rabbi Eliezer ben Ya'akov is measured and clean.
[9] In contrast, Ibn Ezra views Rabbi Eliezer ben Ya'akov's concern as intrinsically related to going out to war:
Ibn Ezra Devarim 22:5
A man's article shall not be - it is connected to because of going out to war…And if she goes out with men to war, along the way she will come to licentiousness…
[10] Sefer Ha-mitzvot of Rambam, Negative Commandment 39
Every woman who decorates herself with one of men's ornaments known in this city as an ornament exclusive to men receives lashes.
[11] Ibn Ezra puts this in stronger terms in his commentary to the Torah (Devarim 22:5). Some later rabbinic figures develop this line of thought further:
Rav Samson Raphael Hirsch, Devarim 22:6, trans. Isaac Levy
The preceding laws (verses 1-5) proclaimed the fundamental principles for the foundation and development of the impending social life of the people. The great principles of solidarity and fraternity in looking after the property, and furthering the undertakings of others, as well as the preservation of the separate professions and ways of life of the sexes. The former form the fundamental pillars of social intercourse, as the latter serve the foundation of the "homes" which indeed are the granite base for all national well-being. In v. 5, already Woman was placed in the foreground in this respect. On that, that lo yihyeh keli gever al isha, which conceives Woman in the loftiness and worthiness of her profession as "Mother of the Home", and in the "limitation" is to stand in the nation, highly respecting herself and being highly respected, protected and unassailable, on that, more than on anything else, the prosperity and the constant progress of the life of the people, is dependent The degree in which the calling of Woman is held in high honour on all sides is an important yardstick by which the moral standard of a nation can be measured.
Rav David Tzvi Hoffman, Devarim 22:5
The Torah said to have mercy on living creatures and on the orders of nature as they were arranged by Heaven ("you shall keep My statutes," Vayikra 19:19), and thus Scripture put adjacent here the mitzva of sending away the mother bird and the mitzva of kil'ayim…Thus it is understood that included in the orders of nature in accordance with the will of the Creator, may His name be blessed, one should count the admonishment to separate between human genders with regard to conduct and clothing. But here failure to keep the orders of nature is liable to lead to acts of abomination, and therefore this transgression itself is called an abomination, and it is more grave than mixing up species of plant and animal nature, for they have no consciousness.
[12] Ibn Ezra seems to understand Rambam's view differently, as a nod to associations between homosexuality and cross-dressing. Ibn Ezra himself rejects this rationale:
Ibn Ezra Devarim 22:5
…There are those who say it concerns homosexuality, and there is no need [to explain it thus]…
[13] Available here: https://hebrewbooks.org/pdfpager.aspx?req=14427&hilite=51f45f35-fab5-4c40-9173-22793c3c4582&st=%d7%9c%d7%94%d7%aa%d7%93%d7%9e%d7%95%d7%aa&pgnum=236
[14] A responsum attributed variously to Rambam or to his son similarly rails against a custom for a bride to wield a sword for a wedding dance.
Novellae of Rambam, from Kovetz Teshuvot Ha-Rambam Ve-iggerotav (Lichtenberg)
Novellae from our great Rav Rambam that his pious son Rav Avraham edited...And the daughters of the children of Israel, even though most have been saved from this iniquity, i.e., the prohibition of there should not be a male article etc., behold some of them stumble in it due to their foolishness, and this is that in their weddings they act like non-Jews  and the woman puts on a turban or hat and takes a sword in her hand and goes out to dance before the men and the women in this abomination, and it should not occur to one that on account of her being a bride a Torah prohibition would be permitted to her, unless they are delivered from this in their relying on the custom...and this already was done in Egypt and great ones would stumble with it until we nullified it and erased its memory...
[15] Rav Zvi Rayzman, Ratz Ka-tzvi, Laws of Chanuka and Purim 36
When his intention is for rejoicing on Purim, even though the fundamental act is resembling a woman, since there is no intention of licentiousness, there is no prohibition. And this rationale applies also in a play, for there isn't intention of licentiousness, and because of this, there is no prohibition, not for wearing and for the consequence of the wearing.
[16] Rav Moshe distinguishes between carrying a personal weapon for self-defense, and bearing arms as a soldier. (His ruling incorporates a novel reading of Rabbi Eliezer ben Ya'akov, that he specifically prohibits a woman wearing a weapon in the way of those who make war, and would thus permit wearing a weapon decoratively).
Responsa Iggerot Moshe OC IV 75:3
In the settlement of Gush Etzion and in other settlements which are adjacent to Arabs, among whom are many haters of Israel and murderers, if one can permit women to bear the weapon called a pistol etc. And one can permit it in accordance with what Taz and Shach wrote in the name of Bach, that if she does it [wears a man's garment] because of the heat or the cold and rains, there is no prohibition. And this weapon is not in the manner of decoration and beautification, but to defend themselves. And there is no concern of going out to war, rather they do it only in circumstances such as traveling on the road. And a small weapon like this is also not the way of the military for war. but rather larger weapons are [military]. this is a reason to permit it. And therefore women are permitted to bear weapons even to save themselves from blows in general, for in this regard women are perforce like men, and it is simple for it is also a matter of preserving life, and it is not relevant to obligate women because of this not to travel where they want. And only to go out to war is not the way of women and they are also prohibited, and so in other places which are considered at peace they are prohibited [to carry weapons].