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Iyun in Shevuot -
Lesson 14

One Who Took An Oath Not to Eat Half a Measure of a Prohibited Item and then Ate a Full Measure

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Sources: In the previous shiur we dealt with the dispute regarding whether a half-measure of a prohibited item falls into the category of "bound by an oath from Mount Sinai." In this shiur we will discuss the opinions that this case is not subject to the rule of "bound by an oath from Mount Sinai. We will also examine the law in the case where a person took an oath not to eat half a measure, and then ate a full measure; is he now liable twice? In this context see Tosafot ha-Rosh, 24b, in the passage cited below (which relates to the Gemara there which states: "For example, if he said: I swear that I shall not eat dates and forbidden fat; since it takes effect with respect to the dates, it takes effect also with respect to the forbidden fat"); and compare with Rashi, Yoma 73b, last two comments. See also Rambam, Hilkhot Shevuot 5:7, and try to understand his approach.
See Mishna 27b, and the Gemara there until "He is not liable until he eats it all," and Rashi, ad loc. What difficulty arises with respect to Rashi? Is it possible to suggest ways to distinguish between the cases under discussion?
 
Tosafot Rosh, Shevuot 24b:
"It may be asked: Even without an inclusive oath we find it. For example, where he said: I swear that I shall not eat half an olive-sized measure of fat, regarding which he is not bound by an oath from Mount Sinai, and when he eats an olive-sized measure, he is liable for his oath, since an olive-sized measure includes half an olive-sized measure. And it should have said: According to your reasoning."
 
I. A Dispute Among the Rishonim
 
In the previous shiur we saw that according to the plain sense of the Gemara in Shevuot 23b, an oath not to eat half a measure of a prohibited item takes effect, and it is not subject to the limitations of "bound by an oath from Mount Sinai" or the rule that a prohibition does not apply to an item that is already prohibited. This is true even according to Rabbi Yochanan who says that half a measure is prohibited by Torah law. On the other hand, the plain sense of the Gemara in Yoma implies that according to Rabbi Yochanan, such an oath is subject to the rule of "bound by an oath from Mount Sinai." As we have seen, the Rishonim disagree; some follow the plain sense of the Gemara in Yoma, while others accept the plain sense of the Gemara in Shevuot and propose various explanations as to why half a measure is not subject to the rule of "bound by an oath from Mount Sinai." One of these Rishonim is the Tosafot Rosh, who says: "Since it is only a mere prohibition (issura b'alma), it is not called 'bound by an oath from Mount Sinai.'"
 
In the continuation of the Gemara in Shevuot it says that it is possible to overcome the problems of "bound by an oath from Mount Sinai" and the rule that a prohibition does not apply to an item that is already prohibited, with the help of an inclusive oath, and one of the examples of such an oath is as follows: "For example, if he said: I swear that I shall not eat dates and forbidden fat; since it takes effect with respect to the dates, it takes effect also with respect to the forbidden fat" (24b). The Tosafot Rosh (ad loc.) notes that it is possible to impose liability for the oath in addition to the ordinary liability for forbidden fat even without the dates, if "for example, he says: I swear that I shall not eat half an olive-sized measure of fat, regarding which he is not bound by an oath from Mount Sinai, and when he eats an olive-sized measure, he is liable for his oath, since an olive-sized measure includes half an olive-sized measure." The Rosh argues that when a person takes an oath not to eat half a measure of fat, his oath applies to the half-measure, and therefore when he eats a full measure, he is liable both for the oath and for the prohibition of eating forbidden fat.
 
            The Rosh's argument that after swearing "I shall not eat half an olive-sized measure of forbidden fat," one who eats an olive-sized portion of fat is liable on two counts seems obvious, even if it raises a certain difficulty with the words of the Gemara, as noted by the Rosh.
 
However, the words of Rashi in Yoma suggest a different approach. Rashi comments on the words of Resh Lakish: " You cannot solve [this problem] except either if he expressly states half a measure, in accordance with the view of the Rabbis; or, if his oath is undefined, in accordance with the view of Rabbi Akiba, who says, a man [in an undefined oath] prohibits to himself even a minute quantity." Rashi writes as follows:
 
Or if his oath is undefined – You can explain it that way; however, when he eats of it, he eats only half a measure, regarding which he is not bound by an oath from Mount Sinai, and by swearing that he will not eat with an undefined oath it becomes forbidden to him.
 
Rashi disagrees with the Rosh and says that even if an oath applies to half a measure, because the prohibition of half a measure doesn't fall into the category of "bound by an oath from Mount Sinai," this is only true of a person who eats half a measure and no more. But if he eats a full measure, we do not regard him as one who ate half a measure of forbidden fat, and then continued to eat up to a full measure, but rather as one who violated the prohibition to eat forbidden fat. Regarding this eating as a unified whole, he was bound by an oath from Mount Sinai, and therefore the oath that he took does not apply. It turns out then that when he ate the first half-sized measure, it was possible to see him as one who violates the prohibition of an oath, but when he continued and ate the second half-sized measure, we understand retroactively that he should be viewed as one who ate an item that is fully prohibited by Torah law and to which an oath does not apply.
 
It should be noted that Rashi may have said what he said only with regard to an undefined oath of "I shall not eat," according to Rabbi Akiva, who says that such an oath prohibits even half a measure. Regarding an oath of "I shall not eat," there is room to say that it applies to a person's eating, regardless of the measure. When he stops after eating half a measure, this is eating, and his oath applies to such eating. When he stops after eating a full measure, this is still eating, but to such eating his oath does not apply, since he is already bound by an oath from Mount Sinai. As for the first possibility proposed by Resh Lakish, that we are dealing here with a person who swears "I shall not eat half an olive-sized measure of fat" (according to the view of the Rabbis that an undefined oath does not prohibit half a measure), it is possible that Rashi would agree that the oath relates to half an olive-sized measure as half an olive-sized measure, and it applies because it does not fall into the category of "bound by an oath from Mount Sinai," and it does not become canceled even when the person continues and eats a full measure.
 
It may be added that the Rambam (Hilkhot Shevuot 5:7) writes: "[When a person says:] I swear that I will not eat even the slightest amount of a neveila or a tereifa, and he ate less than an olive-sized portion, he is liable for a [false] oath, for he is not bound by an oath from Mount Sinai for half a measure." It may be inferred from his words that he agrees with Rashi, that he is only liable if he ate half a measure. Rabbi Akiva Eiger read the Rambam this way in his responsa (no. 76, no. 154), while emphasizing two points:
 
1. A distinction can be made between a person who swallows an olive-sized portion all at once, as he is treated as one who ate only a full measure, and one who ate half an olive-sized portion, stopped and then within the time that it takes to eat a peras, he continued and ate another half an olive-sized portion, regarding whom it would be more novel to say that the liability for a false oath that applied to him after the first stage disappeared after he completed eating a full measure. It is possible that the Rambam comes to exclude only the first case.
 
2. There is room to ask why shouldn't an oath "not to eat any amount of neveilot and tereifot" - which includes the case of half an olive-sized measure and the case of a full olive-sized measure – apply based on the law of an inclusive oath, and so there should be liability for a false oath even for eating a full olive-sized portion.[1] Rabbi Akiva Eiger explains as follows: "It is only called an inclusive oath if it includes a different type, but if it includes eating the same thing in a different manner, this is not called an inclusive oath." There is room for further discussion regarding this distinction, but this is not the forum for that.
 
II. The Objection From the Gemara on P.27b
 
An explicit Gemara on p. 27b would appear to support the view of the Rosh. The Gemara there brings the words of Rava, that when a person swears that "I shall not eat this loaf," he is liable even for eating an olive-sized measure of it, but if he swears that "I shall not eat it," he is only liable if he eats the entire loaf, because in that case his words are interpreted as prohibiting the loaf as a unit. And the Gemara says that if a person swore that "I shall not eat this loaf" and then he swore that "I shall not eat it," the second oath is an oath to fulfill an oath and does not apply; but if he first swore that "I shall not eat it" and then he swore that "I shall not eat this loaf," in which case the second oath added a prohibition to eat an olive-sized measure of the loaf, the second oath applies, and when the person eats the whole loaf he is liable for two false oaths. Rashi explains: "When he eats the first olive-sized portion – he is liable for the second oath; and when he finishes eating it, he is liable for the first oath." This seems to prove that when an oath applies because it relates to a measure smaller than that regarding which the person had already been bound by an oath from Mount Sinai, it applies even when the person eats the larger measure. This runs counter to what Rashi says in Yoma (this difficulty is raised in Responsa Zikhron Yehonatan, Yoreh De'a, no. 4, against the words of Rabbi Akiva Eiger, referred to earlier).
 
However, as we saw above, regarding the Rambam, it may be suggested that the exemption applies only in the case where he ate the full measure at once, for then no liability is imposed upon him for the half-measure; and it may be proposed that the liability for two false oaths mentioned in the Gemara on p. 27b is only in the case where he ate in two stages. This is what is implied from the aforementioned words of Rashi, and so too from the words of the Rambam: "He is liable [for the latter oath] when he eats an olive-sized portion. And when he eats the entire [loaf] he is liable for his first oath" (Hilkhot Shevuot 4:10; and compare Rabbeinu Chananel, ad loc., who does not mention this). However, the words of Rashi in Yoma imply that even when the person eats in two stages he is not liable for eating the half-measure, and so his position requires further examination.
 
III. Possible Distinctions Between the Cases
 
We will examine several possible ways to distinguish between the cases.
 
 As we saw above, it is possible that the position of Rashi in Yoma was only proposed in the case of an undefined oath of "I shall not eat" according to Rabbi Akiva who maintains that such an oath prohibits even less than an olive-sized measure. When a person explicitly swears that he will not eat half a measure, his oath applies to the half-measure as a half-measure, and it is not cancelled when he continues to eat the full measure. According to this, there is room to say that the oath that "I shall not eat this loaf," which forbids an olive-sized portion, is an oath that relates to a unit the consumption of which is defined as an act of eating, as opposed to the first oath that forbade the loaf as a unit. Therefore, the fulfillment of the factual foundation of the narrow oath is not blurred when the factual foundation of the oath relating to the larger measure is fulfilled.
 
Another possibility is to distinguish between an oath regarding less than an olive-sized portion, which is discussed in Yoma, and an oath regarding an olive-sized portion which is discussed in Shevuot 27b. When a person takes an oath regarding less than an olive-sized portion, and then eats an olive-sized portion, the eating of the olive-sized portion is bears a new definition, as a full act of halakhic eating. In such a situation, we do not say that in practice he both ate less than an olive-sized portion (thus transgressing the oath) and he ate an olive-sized portion (thus transgressing the prohibition of eating fat); rather we see the situation differently - there was an event involving a halakhic act of eating, and the event of eating less than an olive-sized portion did not take place. In contrast, when a person creates a new concept of eating an entire loaf, this does not supercede the ordinary concept of eating an olive-sized portion, since both are acts of eating. Therefore, even when he eats the entire loaf, we say that two events took place and therefore he is liable for two transgressions.
 
A third possibility was proposed by some of the leading Torah authorities of the previous generation: the Steipler[2] and R. Shemuel Rozovsky.[3] According to them, the difference between the passages stems from the fact that in the Gemara in Yoma (and in Shevuot 23b) we are dealing with the rule of "bound by an oath from Mount Sinai" in relation to a Torah prohibition, such as neveilot and tereifot; whereas in the Gemara in Shevuot 27b we are dealing with the rule of "bound by an oath from Mount Sinai" in relation to a prohibition following from an oath. The distinction is of course with respect to the larger measure, which is subject to the earlier prohibition. R. Shemuel says as follows:
 
The prohibition of neveila is different than the prohibition of an oath. For where he eats neveila in [the prohibited] measure, and there is eating in measure, every morsel is subject to the prohibition of "You shall not eat neveila," for every partial eating is part of the prohibited action. It turns out that for this kind of eating, he had already been subject to a prohibition because of the prohibition of neveila, and therefore even if he ate an olive-sized portion of neveila one after the other within the time that it takes to eat a peras, he is not liable for the oath, for in such a case he was already bound by an oath from before, and in this case there is no prohibition of half a measure, but rather it is part of the prohibition of eating a full measure. But in the case of an oath, when he took an oath not to eat the entire loaf… when he ate the entire loaf, each little portion is not a segment of the prohibited action, but rather the entire prohibition is that he transgressed his oath and ate the entire loaf. Eating the entire loaf is what is prohibited, but for each little part there is no prohibition, and therefore he is liable for two. 
 
What this means is that when a person eats a full measure of neveila, the forbidden action of eating a halakhic measure of neveila began already when he started to eat, and therefore the entire process is seen as an organic unit, regarding which a person is bound by an oath from Mount Sinai. With respect to the prohibition of an oath, on the other hand, there is no gradual building up of the prohibition. As long as he had not completed the act that is prohibited by the oath (to eat an entire loaf), there is no false oath or breaking of his word. These come into existence when he crosses the finishing line and completes the action prohibited by the oath. Therefore, there is nothing preventing us from saying that the beginning of the action is a breaking of the oath relating to the smaller measure and the end of the action is a breaking of the oath relating to the larger measure, and thus he is liable for two.
 
This last suggestion brings us back to questions that were raised throughout the course of this series of shiurim. If we understand that the problem with an oath relating to the future stems from the falsehood, it is clear that a partial breaking of the oath is not included in the prohibition, because the oath was not false. Even if we understand that the oath established a new law, but this law is binary (that is to say: either one transgresses it or it is altogether permitted) and does not constitute a continuing process of prohibition similar to forbidden foods, then we can easily understand the proposed distinction. For this we must adopt the positions of the Rishonim who said that the prohibition of half a measure does not apply to an oath.[4] But can we adopt the proposed distinction even according to the Rambam, who writes that eating less than an olive-sized portion of an item prohibited by a vow is "as if he partook of less than the minimum measure of a neveila, a tereifa, or the like" (Hilkhot Shevuot 4:1)?
 
As we saw in shiur no. 6., it follows from the Ran that the Rambam's position is not based on an understanding that sees the course of the oath as a continuing prohibition, but rather on the idea that any action the continuation of which can lead to a complete prohibition is defined as a prohibition of "half a measure," whether because of the concern that perhaps the person will continue the action, or for some other reason. According to this, we can still adopt R. Shemuel's distinction, because there is room to argue that eating part of a larger measure is not defined as an action regarding which a person is bound by an oath from Mount Sinai, even after he completes the larger measure.
 
In that same shiur we noted a different understanding of the Rambam, according to which the Rambam is dealing specifically with a person who forbids the action to himself with the undefined wording of "eating." As we saw in that shiur, it is very possible that the Rambam agrees that when it is clear that a person has in mind to forbid a particular measure, there is no room for the prohibition of half a measure for less than that. We saw then that the Rambam's position is that the view of the Sages that was accepted as the Halakha, that a person who swears that "I shall not eat" is not liable for less than an olive-sized portion, is not based on our interpretation of the swearer's intention, that he did not intend to forbid himself less than an olive-sized portion, but rather on the fact that we apply to oaths the same parameters that apply to Torah prohibitions of eating, that there is no liability for less than an olive-sized portion. Therefore, it is incorrect to say that eating less than an olive-sized portion is included in the oath, because the person swore in an undefined manner that he would not eat. When a person takes such an oath, the Halakha takes over and says that an important act of eating that bears liability requires an olive-sized measure, whereas eating less than an olive-sized measure is included in his oath and therefore forbidden by Torah law, but it bears no liability, similar to ordinary Torah prohibitions. As we noted, there is a novel point here, for on the face of it, if this is included in his oath, it is difficult to understand why he is exempt from lashes and a sacrifice, for a person can forbid by way of an oath even actions that are not recognized in the world of Halakhic prohibitions (and it stands to reason that it is for this reason that the Ran did not explain the Rambam in this manner). But it seems that the Rambam understood that there is gradation among the things that are included in the person's oath, and that from a certain level and on there is a complete cancelling of his oath which leads to liability for lashes and a sacrifice, but until that level there is only the prohibition of half a measure as is found in the rest of the Torah.
 
For our purposes, according to the last understanding that we saw in the Rambam, if we adopt the view of Rashi, that when a person takes an oath not to eat half an olive-sized measure of neveila, and then he ate a full measure, he is only liable for the prohibition of eating neveila, but not for the prohibition of a false oath; we can activate a similar mechanism also with respect to an oath, and say that if a person takes an oath not to eat an olive-sized portion of bread, and then he takes another oath not to eat half an olive-sized portion of bread, and the he ate a full olive-sized portion, he is only liable for one oath, for eating the full olive-sized portion, because he was bound by an oath from Mount Sinai regarding the eating of the olive-sized portion similar to neveilot and tereifot. However, this does not negate R. Shemuel's explanation of the Gemara in Shevuot 27b. There we are dealing with an oath regarding a large measure which is not an expression of an undefined oath that "I shall not eat," but rather an oath relating to a measure that is defined with respect to the loaf: "I shall not eat it." Regarding such an oath the Rambam, as stated, agrees that there is no prohibition of partial eating, and therefore we can certainly say that the food was not included in the category of "bound by an oath from Mount Sinai" regarding eating part of it, because of its leading to eating all of it. Thus we see that the distinction is possible even according to the Rambam.
 
(Translated by David Strauss)
 

[1] It should be noted that the Rosh, who disagrees with Rashi and says that in such a case the person is liable even if he eats a full olive-sized portion, does not say that the liability is based on the law of an inclusive oath.
[2] Kehilot Yaakov, Shevuot, no. 19.
[3] Chiddushei R. Shemuel, Kuntrus be-Inyan Nedarim u-Shevuot le-Vatel et ha-Mitzva, no. 6, 1.
[4] As is brought by the Ran, p. 9a in Alfasi in the name of "There are those who say": "This is not similar to the rest of the prohibitions in the Torah, regarding which we hold like Rabbi Yochanan who said in the last chapter of Yoma, that half a measure is prohibited by Torah law. But here it is a prohibtion that comes of its own accord, and since his intention was only for an olive-sized portion, less than an olive-sized portion is totally permitted."
, full_html, In this shiur we will examine the law in the case where a person took an oath not to eat half a measure of a prohibited item, and then ate a full measure; is he now liable twice?

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