What is a guf naki? How is it connected to tefillin, and to women?
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By Laurie Novick
Rav Ezra Bick, Ilana Elzufon, Shayna Goldberg, and Rav Da'vid Sperling, eds.
The Sanctity of Tefillin
Verses from the Torah, written on parchment (kelaf) by a scribe, including God’s name, have tremendous sanctity. It might seem almost like an act of spiritual arrogance for an ordinary person to lay tefillin, which contain such verses. How can one be certain of maintaining the level of care and respect necessary for these verses to rest on the body? Yet the Torah commands that tefillin be worn on every workday. The halachot of tefillin reflect the serious responsibility that this mitzva entails.
The sanctity of tefillin dictates the behavior of the person wearing them:
Rabba bar Rav Huna said: A person must feel his tefillin at all times, a fortiori from the tzitz [on the forehead of the Kohen Gadol]. If concerning the tzitz, which only has one mention of God's name, the Torah says "It should be on his forehead always," that he not distract his thoughts from it, how much more so tefillin, which have many mentions of God's name.
The garments of the Kohen Gadol include the tzitz – a gold plate on his forehead, inscribed with the words “Holy to God.” When wearing the tzitz, the Kohen Gadol must maintain constant focus and avoid distraction. The gemara tells us that a person wearing tefillin – in which God’s name is written multiple times – has even greater responsibility. He must check the tefillin regularly in order to remain mindful of them and what they represent, and as a precaution against hese'ach ha-da'at, becoming distracted.
Talmidei Rabbeinu Yona explain that this does not mean that a person wearing tefillin must think of them at every moment, but rather that frivolous thoughts must be avoided.
Talmidei Rabbeinu Yona on the Rif, Berachot 14b
Certainly hese'ach ha-da'at is only when one is in a state of frivolity and silliness, but when one stands in awe [of God] and occupies himself with his needs, even though he is occupied with his trade and his needs and his thoughts are not specifically on them [the tefillin], this is not called hese'ach ha-da'at.
Thoughts with seriousness of purpose, even if not concerning tefillin, are not considered hese'ach ha-da'at. In contrast, frivolity is antithetical to awe of God and cannot co-exist with laying tefillin.
The sanctity of tefillin
demands that one maintain cleanliness. For example, when laying or handling tefillin
, a person cannot be soiled with excrement or semen.
The Talmud teaches that the requirement of guf naki (lit. clean body) applies when wearing tefillin and extends beyond simple cleanliness.
Rabbi Yannai said: Tefillin require a guf naki, like Elisha Ba'al Kenafayim. What is it (guf naki)? Abbaye said: That he not pass gas in them. Rava said: That he not sleep in them. And why is he called Ba’al Kenafayim? Because once the wicked Roman government decreed on Israel that the brain of anyone who lays tefillin will be perforated. Elisha would lay them and go out to the marketplace. A quaestor saw him. He [Elisha] ran away from him and he ran after him. When he [the Roman] reached him, he [Elisha] took them off his head and held them in his hand. He said to him [Elisha]: What is that in your hand? He [Elisha] said to him: Dove’s wings. He opened his hand, and there were dove’s wings. Therefore, he is called Elisha Ba’al Kenafayim [Elisha Man of wings].
demands constant vigilance. Passing gas violates the requirement of guf naki
, and so does falling asleep, which might lead to uncontrolled flatulence or to involuntary emission of semen.
Elisha Ba'al Kenafayim merited a miraculous deliverance from Roman persecution, apparently because he was especially careful to maintain guf naki
Maharam of Rothenburg, a towering halachic authority of thirteenth century Ashkenaz, is particularly stringent about guf naki requirements, and extends their scope. For example, he maintains that guf naki also requires a person to keep thoughts free of sexual fantasy when donning tefillin. Out of concern for guf naki, he does not permit men to lay tefillin if they cannot control fantasizing.
Orchot Chayyim I Tefillin 3
Maharam wrote about the young men about whom you asked, who fantasize even at the time of reciting Shema, that they should not lay tefillin. Even one with a digestive problem or who cannot control his orifices without difficulty is prohibited from laying them. How much more so that he not act in them with frivolity of desire for women.
Rema codifies this position, extending guf naki
from the realm of the purely physical to include thought.
Guf Naki and Non-Observance
Grave concern about guf naki
can explain a surprising chapter in the historical development of the mitzva of tefillin
. In theory, tefillin
ought to be worn all day long. In practice, sources ranging from the Talmud to medieval texts imply that many men did not lay tefillin
, not even for Keri'at Shema.
Tosafot Shabbat 49a s.v. ke-Elisha
…It is not surprising that this mitzva is weak in our hands, for even in the days of the sages it was weak…
An unattainable ideal of maintaining a guf naki
all day long may have deterred the masses from wearing tefillin
Orchot Chayyim, I Tefillin 1
Further, our rabbis taught that the transgressors of Israel through iniquity of their bodies are judged for twelve months in Gehinnom. This applies to one who did not want to lay them [tefillin] because of disdain for the mitzva. But one who avoided them out of fear that he would be unable to maintain his cleanliness and out of respect for the mitzva is not included among them.
Early halachic authorities fought against the abandonment of this mitzva. Since tefillin
should at least be worn during recitation of Shema
, they argued that the average person could maintain a guf naki
and for the remainder of morning prayers.
From the late Middle Ages, common practice (except for uniquely pious individuals) limits tefillin to the morning prayers, and attributes that limitation to concern for a guf naki. Shulchan Aruch makes this case:
Shulchan Aruch OC 37:2
The mitzva [of tefillin] is for them to be on all day. But since they require a guf naki, that he not pass gas in them and that he not be distracted from them, and not every person is able to be careful with them, the practice is not to lay them all day long. In any case, each person needs to be careful to have them on at the time of keri’at Shema and prayer.
Guf Naki and Women
We saw previously
that Michal, the daughter of Shaul, wore tefillin
. The Talmud Bavli states that the sages did not protest; the Talmud Yerushalmi
states that they did.
How can those who claim that women may lay tefillin voluntarily, in line with the Bavli, explain the Yerushalmi’s report that the sages protested Michal's laying of tefillin? What rationale could be significant enough to warrant protest but not enough to warrant it globally? Ri (Rabbeinu Yitzhak of Dampierre, a leading tosafist and a nephew of Rabbeinu Tam) provides an answer:
Eiruvin 96a Tosafot s.v. "Michal"
It makes sense to explain that the rationale of the one who says that it was not permissible [for Michal to lay tefillin voluntarily] is because tefillin require a guf naki, and women are not scrupulous to be careful.
Ri suggests that women are not careful to maintain a guf naki
, and that this may be the basis for the opinion that prohibits women from wearing tefillin
● Are women really less careful about guf naki than men?
It is hard to imagine that Ri is suggesting that women have more difficulty controlling flatulence than men.
What does he have in mind, then? Here are three possibilities:
I. Hygiene: Ri might have had in mind soiling from menstruation, from post-coital discharge, or from involvement in childcare (handling diapers and the like). Maintaining hygiene was more of a challenge nine hundred years ago than now. With the advent of more advanced hygiene products, issues of this sort have been greatly reduced, but not eradicated.
II. Distraction: Ri might think it more likely that women would have hese'ach ha-da'at than men, perhaps because it would often be more difficult for a woman involved with children to free herself of distractions.
III. Volunteer Laxity: Perhaps Ri is making a more conceptual claim, that a person performing a mitzva voluntarily is more likely to be lax with the halachic requirement of guf naki then someone who is obligated to perform the mitzva, and therefore more likely to be attuned to the letter of the law.
Although Ri does state elsewhere that women should not lay tefillin
this comment is not a ruling
about women's voluntarily laying tefillin
. Rather, it is an attempt to understand why anyone would object to Michal's action. Just as scrupulousness regarding guf naki
might explain men's non-observance of tefillin
, it might also explain protest of women's observance of tefillin
Guf Naki and Obligation
Ri's precise language merits attention. He does not state that 'women are not careful (ein zehirot) about cleanliness.' Instead, he asserts that women are not scrupulously attentive to taking care (ein zerizot lizaher) about tefillin's requiring a guf naki.
Perhaps Ri maintains that, being exempt from tefillin
, women might have less awareness of the need to be careful about guf naki
than those who are obligated.
Ritva suggests an idea along these lines.
Ritva Kiddushin 31a
According to Rabbi Yehuda, they protested it because tefillin require a guf naki like Elisha Ba'al Kenafayim (Shabbat 49a) and women have neither cleanliness of body nor cleanliness of mind. According to the sages, they neither protested [nor condoned it]. They did not condone because perhaps they [women] would not take care of them well, and they did not protest because perhaps, since they kept the mitzva regularly, they were careful with them.
Our sages' caution about the sanctity of tefillin means that even those who did not protest Michal's laying tefillin did not really support it. However, Ritva sees a woman's tendency to frivolity or lack of vigilance, leading to deficiency in guf naki, as situational rather than inherent. A woman who is vigilant with the mitzva can achieve guf naki.
Roughly four hundred years later, Magen Avraham takes this argument a step further:
Magen Avraham 38:3
Since they require a guf naki and women are not scrupulous to take care. But if they [women] were obligated, they would not be exempted for this reason, since they would be mindful to take care.
According to Magen Avraham, were a woman obligated in tefillin, she would presumably keep in mind to be sufficiently careful about guf naki. But we cannot assume that a person performing the mitzva voluntarily will pay scrupulous attention to the requirement.
On these readings, guf naki concerns may have less to do with hygiene or with gender than with the effects of obligation on careful practice.
Aruch Ha-shulchan also highlights the relationship of obligation and guf naki, from a different perspective:
Aruch Ha-shulchan, OC 37
Men, who are obligated, must be careful with them at the time of keri’at Shema and prayer and thus do not lay tefillin all day, as I wrote in the prior section. If so, women, who are exempt, why should they bring themselves into such a great concern? For them, the time of keri’at Shema and prayer are like the rest of the day for men. Therefore, we do not permit them to lay tefillin. Even though it was taught in a baraita in Eiruvin 96a that Michal daughter of Shaul would lay tefillin and the sages did not protest her, we do not learn from that, because presumably they knew that she was a totally righteous woman and she knew to take care [about guf naki].
Men are obligated to wear tefillin when reciting Shema. The force of that obligation overrides concerns that they may not succeed in maintaining a guf naki. We trust men to maintain a guf naki while praying, because they have no choice but to fulfill their obligation. But men are strongly discouraged from wearing tefillin beyond that minimum amount of time.
Neither men nor women should take an unwarranted halachic risk by wearing tefillin when there is no obligation to do so. Thus, since women are exempt both from tefillin and from Shema, women should avoid laying tefillin at any time.
Aruch Ha-shulchan emphasizes gender distinctions in mitzva obligation, as opposed to essential gender differences with relation to hygiene or meticulousness. Tefillin are so sacred that only obligation can allow for laying them. No one has an absolute right to lay tefillin.
Aruch Ha-shulchan also suggests that Michal's famed righteousness made her unique. Maharshal, too, explains Michal's laying of tefillin
by writing that a rare combination of piety and practical circumstances gave her an advantage over other women regarding guf naki
Yam Shel Shelomo, Kiddushin, 1:64
They did not protest Michal because she was a totally righteous woman, and the wife of a king, also she had no offspring, and she was able to keep herself in cleanliness, which is not so for other women.
Both authorities allow for the theoretical possibility that an exceptional woman would be able to take proper care to maintain a guf naki.
The requirement of guf naki, meant to respect the sanctity of tefillin, comes to dominate discussion of the mitzva and limit opportunities for fulfilling it. Ultimately, women and men, with little exception, shy away from laying tefillin as much as possible.
In our next installment, we explore how the discussion of guf naki affects halachic rulings on women and tefillin.
 Shulchan Aruch OC, Laws of Tefillin, 40:7
If he slept in them [tefillin] and had a seminal emission, he should not hold the compartments but hold the straps and remove them. Rema: Until he cleans the semen off himself and washes his hands.
 Tosafot, Shabbat 49a, s.v. "Ke-Elisha"
Therefore, he specified Elisha, for presumably since a miracle was done for him with tefillin, he was careful with them and he had a guf naki.
See however, Rabbeinu Chananel, who, based on the context of the Elisha story, limits guf naki requirements to someone laying tefillin at a time of persecution, like Elisha's—a time when most Jews should not risk laying tefillin unless they can meet high standards, like guf naki. This position is not followed as halacha.
Rabbeinu Chananel Shabbat 130a
Our rabbis explained that Rabbi Yannai only spoke of a time of persecution.
If it is impossible without [sexual] fantasies, it is better that he not lay them.
Semag Positive Mitzvot 3
…Thus I expounded this portion among the exiled of Israel to prove that each and every one is obligated in tefillin…
For a summary, see Efraim Kanarfogel, “Rabbinic Attitudes Toward Non-observance in
the Medieval Period,” in Jewish Tradition and the Nontraditional Jew, ed. Jacob J. Schacter (Northvale: Jason Aronson, 1992), pp. 3-36.
A simple reading of the Talmud Yerushalmi suggests another explanation, that charlatans would create a false impression of their own virtue by laying tefillin.
Yerushalmi Berachot 2:3
Why did they not keep them [the mitzva of tefillin]? Because of the charlatans.
An alternative explanation (see Penei Moshe ad loc.) is that the Yerushalmi is asking: 'Why did they not assume those who wore tefillin were trustworthy?'
 Rosh, Hilchot Tefillin 28
Nowadays that we are only accustomed to laying them at the time of prayer, a person can easily be careful at that time
Also Pesikta Rabbati
Rabbeinu Tam suggests an alternative answer, that in the Yerushalmi's version of the story, Michal followed the opinion that one should wear tefillin
on Shabbat and the sages protested because this caused her to violate the rabbinic prohibition of carrying on Shabbat:
Sefer Ha-yashar, Responsa 65:4
Michal's laying of tefillin was on Shabbat, and she followed the opinion that Shabbat is a time to lay tefillin for one who is obligated. For a woman, it is a rabbinic prohibition, for it is not an adornment for her [to be considered permissible to wear on Shabbat].
 Tosafot Eiruvin 96b s.v. Lo
For women and bondsmen in the matter of tefillin are like minors when they have not yet reached the age of educability, that if they want to lay them we do not allow them to because it [might lead to] a disgrace to tefillin.
Indeed, elsewhere (ibid.), Ri compares a woman laying tefillin
to a child prior to the age of educability, who clearly lacks knowledge about the halachot.
This is an expansion of Ramban's explanation ad loc.
And Michal daughter of Sha'ul had no child until the day of her death.
This verse may suggest either that she was amenorrheic or that she had no little children to soil her. This would have made it easier for her to achieve a guf naki than for most women.
Rav Rachamim Falaji suggests that it means that her soul was male, so that kabbalistic objections to women laying tefillin would not apply to her.
Yafeh La-lev 38:2
One can say that Michal bat Sha'ul was a wise woman and knew of herself that she had a soul from the realm of the masculine, and for that reason "Michal daughter of Sha'ul had no child."
Rav Shemu’el ben Yosef (seventeenth-century Krakow) argues that a woman who is menopausal and can maintain a guf naki may lay tefillin, even if she is not exceptionally pious.
Olat Tamid 38:4
Nevertheless, our statement that the sages did not protest her [Michal] implies that if a woman is menopausal and we know she knows to be careful [with guf naki], we should not protest her.
It is important to note that he does tell us if a woman who menstruates, can maintain a guf naki. In any case, Magen Avraham 38:3 rejects this position.