Shiur #04: The Minimum Measure of Eating and Eating Less than this Measure – Introduction

  • Rav Shmuel Shimoni
 
PLEASE PRAY FOR A REFUA SHELEIMA FOR OUR ALUMNUS
CHAIM BINYAMIN BEN RIVKA HINDA, RABBI CHAIM STRAUCHLER,
INJURED BADLY IN A CYCLING ACCIDENT.
 
 
Since we wish to continue our clarification of the definition of the prohibitions relating to a false oath, we will not be dealing at this stage with the Gemara's discussions at the beginning of the chapter, but rather we will continue to clarify the dispute between Rabbi Akiva and the Sages at the end of the first Mishna, which is discussed in the Gemara on p. 21b.
 
            As an introduction to an examination of this dispute, which is connected to the question whether or not eating less than the size of an olive is considered an act of eating, this shiur will examine this conceptual issue, without getting into the discussions found in our chapter, with the hope that this study will provide us with tools that will help us in the future.
 
Sources:
 
1. Makkot 13a: "How much tevel is one to eat to become liable? Rabbi Shimon says: The merest morsel. The Sages say: The size of an olive." (We will soon deal also with the disagreement between them concerning eating a full creature.) See the discussion regarding Rabbi Shimon's view on p. 17a, before the Mishna: "Rabbi Shimon…"; Rashi, s.v. kakh machloket; Ritva and Chazon Ish (below); Tosafot, Shevuot 21b, s.v. velo amru, "… lo havi ela be-ke-zayit."
 
2. Yoma 74a: "Gufa, chatzi shiurasmakhta be-alma; Tosafot, s.v. keivan; [Ramban, Torat ha-Adam (below); Tzelach (below).
 
Ritva, Makkot 17a:
"'Rabbi Shimon says: Any minute quantity is sufficient for lashes; the olive-size mentioned by the Rabbis is required only for a sin-offering.' It was explained that he had a tradition about this. And Rabbeinu Meir, z"l, gave a reason: Regarding lashes, since he ate deliberately, he attached significance to become liable even for the merest morsel. But regarding a sin-offering which is brought for inadvertent eating, we require the size of an olive to attach significance."
 
Chazon Ish, Choshen Mishpat, Likkutim, no. 23, on Makkot 17a:
"'Rabbi Shimon says: Any minute quantity is sufficient for lashes; the olive-size mentioned by the Rabbis is required only for a sin-offering.' The Ritva wrote in the name of the R. Meir: 'Regarding lashes, since he ate deliberately, he attached significance to become liable even for the merest morsel. But regarding a sin-offering which is brought for inadvertent eating, we require the size of an olive to attach significance.' This does not mean that it was pleasurable for him to eat the merest morsel. For if he ate it inadvertently, thinking that it was kosher meat, it was also pleasurable for him to eat the merest morsel. And furthermore, if he ate the merest morsel, he is immediately flogged, even if it was not his intention to stop. Rather he means that one who eats deliberately is punished for his rebellion against the Torah's command, and even when he eats the merest morsel his rebellion is great and he is worthy of punishment. But where he acted inadvertently, so that he requires atonement for his stumbling into eating forbidden fat, we require a minimum measure. This is also indicated by the wording of the Ritva."
 
Ramban, Torah ha-Adam, Sha'ar ha-MichushInyan ha-Sakana:
"Even if she needs a full measure, we feed her in amounts that are less than the full measure, so that they not join to the size of an olive in the time of eating a peras. So rules the author of the Halakhot. It would appear that we do this also for a sick person in order to reduce the prohibitions that carry liability for excision and lashes to mere prohibitions. You might ask: If so, why do they say that we feed him food, the prohibition of which is the least severe. Tevel or teruma, we feed him teruma. But surely regarding both of them it is merely a prohibition (without punishment). Nevertheless, since when eaten in the full measure, the one prohibition is more severe than the other with respect to their punishments, so too when eaten in less than the full measure, the severity of the one prohibition is greater than that of the other. Alternatively: There we are dealing with a case where they assessed him that he requires a full measure, and he needs that the food be joined to form a full measure."
 
Tzelach, Pesachim 44a:
"At the beginning of the last chapter of Yoma it is explained that the reason that Rabbi Yochanan says that a half measure is forbidden by Torah law is 'since it could be joined.' According to this, in the case of a prohibition that is time bound, e.g., chametz on Pesach, where he ate less that a measure on the seventh day, in such a way that there was no time left to eat any more [on the seventh day] in order to complete the measure, this cannot be derived from 'any fat,' and therefore the Rambam derives it from 'You shall not eat.'"
 
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Shiur #4: The Minimum Measure of Eating and Eating Less than this Measure – Introduction.
 
Introduction
 
            In the previous shiurim we began to clarify the parameters of the prohibition of swearing falsely, with special emphasis on the basis for liability in the case of an oath relating to the future. At this stage, we will skip the discussions at the beginning of the chapter, and especially the passage dealing with hatfasa, much of which deals with a clarification of the essence of a vow and the relationship between a vow and an oath. We will move directly to the passages dealing with the dispute between Rabbi Akiva and the Sages, because this will continue the discussion with which we started this series of shiurim. Today's shiur will not deal with this issue directly, but rather it will serve as an introduction to the issues that we will be discussing in various contexts in the upcoming shiurim. The opening Mishna in our chapter records a dispute between Rabbi Akiva and the Sages concerning a person who swears that he will not eat, whether he breaks his oath with even minimal eating or only if he eats food the size of an olive (ke-zayit). We will not clarify this dispute today, but rather we will preface that clarification with a general discussion concerning the definition of the act of eating, and the role of the measure of a ke-zayit in this context. I hope that the points to be discussed in this shiur will provide us with tools that will serve us later in our study.
 
The Rambam writes:
 
The minimum measure for which one is liable for partaking of any of the forbidden foods in the Torah is [the size of] an average olive. [This applies] whether for lashes, excision or death at the hand of heaven…
This measure, as all the other measurements, is a halakha conveyed by Moshe from Sinai. It is forbidden by Scriptural Law to eat even the slightest amount of a forbidden substance. Nevertheless, one receives lashes only for an olive-sized portion. If one partakes of any amount less than this measure, he is given stripes for rebellious conduct. (Hilkhot Ma'akhalot Asurot 14:1-2)
 
It is necessary to examine whether the measure of ke-zayit, which is a Halakha conveyed by Moshe from Sinai, is a quantitative measure, that is to say, that even if one eats less than the size of an olive, he is regarded as having performed an act of eating, but the Halakha conveyed by Moshe from Sinai teaches that punishment is imposed only if one eats a significant amount of food, namely, a ke-zayit; or perhaps the size of an olive is a quantity that defines quality – without this minimal measure, the act of swallowing is not defined as an act of eating.
 
[As an aside, according to the alternative that the measure of ke-zayit is a condition for defining the action as an act of eating, it may be asked whether alongside this requirement there is also a quantitative requirement to eat a ke-zayit of the forbidden food. The Gemara in Pesachim 43b cites a view according to which "a permitted commodity joins a prohibited commodity," which according to Rashi means that that liability can be imposed if one ate half the size of an olive of a prohibited food and half the size of an olive of a permitted food, if they were eaten together.  At first glance, this is a puzzling position, for the person did not eat a ke-zayit of the prohibited food. It would appear that according to this view the measure of a ke-zayit comes only to define an action as an act of eating, and that once the action is defined as an act of eating, even if a ke-zayit of the prohibited food was not eaten, one can become liable for eating a minute quantity. According to this explanation, we must examine the dissenting views, but this is not the forum for such a discussion.)
 
II. The Dispute Between Rabbi Shimon and the Sages
 
            The Gemara in Shevuot 21b, which we will study for the next shiur, cites the exceptional view of Rabbi Shimon concerning the laws of forbidden foods:
 
Rabbi Shimon says: For a minute quantity lashes are administered; the size of an olive is required only for a sacrifice.
 
Rabbi Shimon is clearly not of the opinion that the measure of a ke-zayit is a condition for defining an action as an act of eating, for the Torah says: "You shall not eat any fat or blood" (Vayikra 3:17), and Rabbi Shimon imposes liability for lashes even if one eats less than the size of an olive. What is more, according to Rabbi Shimon, the quantitative measure does not apply with regard to lashes, but only with regard to a sacrifice. What is the reason for this?
 
Rashi, in the parallel passage (Makkot 17a) explains:
 
Rabbi Shimon maintains that regarding all forbidden foods, lashes are administered for a minute quantity, and they spoke of a ke-zayit only with regard to a sacrifice for the inadvertent eating of a forbidden food, the deliberate eating of which bears liability for excision. This is a Halakha conveyed to Moshe at Sinai. (s.v. kakh)
 
According to Rashi, Rabbi Shimon maintains that the Halakha conveyed to Moshe at Sinai relating to the measure of a ke-zayit applies exclusively to liability for a sacrifice, and not to liability for the punishment of lashes.
 
The Ritva proposes a novel idea in the name of the Rama:
 
Rabbeinu Meir explains that regarding lashes, since he ate the food deliberately, he attached significance to his action so that he is liable even for a minute quantity. But regarding a sacrifice, which is brought for an inadvertent act of eating, a ke-zayit is regarded for the action to be considered significant.
 
According to the plain meaning of the words of the Rama, the dividing line is not between lashes and a sacrifice, but between a deliberate and an inadvertent action. When a person intentionally eats a prohibited food, he demonstrates that the prohibited food is significant to him, and this principle of "attaching significance" overcomes the absence of quantity by attaching significance in an alternative manner. It may be asked: From where do we derive this novel idea that intention to transgress a prohibition magnifies the importance of a particular object or action? The Chazon Ish adds to this question:[1] What do we say about a person who intended to eat a ke-zayit of a prohibited food, and then after receiving a warning ate only half a ke-zayit – do we say that such a person did not attach significance to the half of a ke-zayit?
 
The words of the Tosafot in Shevuot indicate a different approach:
 
They required the size on olive only for a sacrifice… for the sacrifice depends of excision (karet)[2], and there is excision for a deliberate transgression only if he ate a ke-zayit.
 
According to the Tosafot, the dividing line does not pass between a deliberate and an inadvertent action, nor between lashes and a sacrifice (as one might understand from Rashi in Makkot), but rather between the punishment of lashes and the punishment of excision. This can be understood according to what the Chazon Ish writes (the Chazon Ish writes this in explanation of the words of the Ritva, but in my opinion, what he writes is more applicable to the position of the Tosafot):
 
One who deliberately eats a prohibited food is punished for rebelling against the Torah, and even when he eats a minute amount, he rebels greatly and is worthy of punishment; but one who eats the prohibited food inadvertently, who requires atonement for having stumbled over the prohibition against eating fat, requires the minimal measure of a ke-zayit.
 
The Chazon Ish refers to a fundamental distinction between two negative components that are found in the transgression of Torah prohibitions. One component is the very rebellion against God's commandment, and the second component is the performance of an action that is inherently negative, adds evil to the world, and pollutes one's soul.  According to the Chazon Ish, Rabbi Shimon maintains that there is rebellion in the very eating of a prohibited food (of course, on the assumption that the action is classified as eating); but the liability for a sacrifice, which falls on a person who sinned inadvertently and did not rebel, relates to the negative aspect of the essence of the act, and for this we require a certain significance which depends on quantity.
 
As stated, in my humble opinion, the words of the Tosafot should be explained in accordance with the approach of the Chazon Ish. The liability for lashes relates to the very act of rebellion and the violation of God's command. On the other hand, the liability for excision does not depend on the very act of rebellion, but on the fact that we are dealing with a transgression of special severity, and therefore it depends also on the essence of the act, and only on a significant quantity. Therefore, the dividing line passes between lashes and excision. 
 
In any case, it is clear that according to Rabbi Shimon's exceptional position, there is an act of eating even with less than the size of an olive. Now we must examine whether the Sages disagree with him on this point, and therefore they impose liability for lashes only if the person ate a ke-zayit, or perhaps they too agree with Rabbi Shimon's fundamental assertion.
 
III. The dispute between Rabbi Yochanan and Resh Lakish regarding half of a measure
 
The Gemara in Yoma (73b-74a) records a dispute about whether eating a minute amount of a prohibited food, less than the minimal measure, is forbidden by Torah law (Rabbi Yochanan) or only by Rabbinic decree (Resh Lakish). As the Tosafot clarify in our passage (Shevuot 21b, s.v. ke-Rabbi), Rabbi Yochanan does not base his view on that of Rabbi Shimon, but rather he maintains that even if punishment is administered only for eating a ke-zayit, there is a Torah prohibition to eat even less than that.
 
Is there any reason to say that even if a quantitative measure is required to administer punishment, it is still biblically prohibited to eat even less than the minimal measure? Ostensibly, the answer is yes – the Torah forbids the very act, but in order to impose punishment it requires a minimal measure. Eating less than the measure of an olive is also a sin, but it does not suffice to impose punishment. In light of this, it is Resh Lakish's view that requires explanation: Why is there no biblical prohibition? The Gemara attributes to Resh Lakish the following explanation:
 
Resh Lakish said: It is permitted by biblical law, for the Torah speaks of eating and this is not [eating].
 
Resh Lakish takes a clear position on the issue that we have raised: Eating less that the measure of an olive is not defined as an act of eating. Therefore, there is no room for the model presented above, according to which a sin is committed even with an offense that is less than the minimal measure, because eating less than the measure is defined as an action of a totally different category than eating the minimal measure for which liability is imposed.
 
Now we must clarify the position of Rabbi Yochanan, the position that has been accepted as halakhically binding, that eating less than the minimal measure is forbidden by Torah law. The Rishonim note the Gemara's duplication in its presentation of the foundation of this position: 1) a logical rationale – "since it could be joined [to form a minimum] it is forbidden food that he is eating". Obviously, this rationale requires explanation. 2) an exposition of the verse that is brought in a Baraita: "I know only that whatsoever involves punishment is subject to a prohibition; but in the case of a koy and what is less than the legal minimum, since they do not involve punishment, I might say that they are not subject to a prohibition either. Therefore the verse states: 'Any fat.'" According to Rabbi Yochanan this is a full-fledged derivation, whereas according to Resh Lakish, this verse is merely a support for a rabbinic law (asmakhta be'alma).
 
In his clarification of this duplication, the Ran in Shevuot writes as follows:
 
Even though there in Yoma they derive the law of half a measure from a textual inclusion, that inclusion was certainly written only in regard to fat. But nevertheless we learn from it with regard to all prohibited foods, for it is obvious to us that the Torah forbids it because it can be joined to form a minimum measure. (Ran on the Rif, Shevuot 9a, s.v. amar)
 
According to the Ran, the exposition was said regarding the prohibition of eating fat, but since it appears to be based on the idea of "since it could be joined," it can be extended to all Torah prohibitions. It is not clear from his wording whether in the end we are dealing with a rule that is based exclusively on logical reasoning, or whether this reasoning teaches us that the exposition applies to all of the Torah's prohibitions.
 
In contrast to the Ran, the Tosafot in Yoma (s.v. keivan) clearly state that the source of the law is the exposition, and that the rationale was needed only to clarify that this is a fully valid derasha:
 
For if we only had the verse of "Any fat," I would have thought the verse was needed for a koy, and the law of half a measure is only a rabbinic measure that was made to hang on a verse. But now that it says that the rationale is that it could be joined, it is reasonable to say that this is a fully valid derasha for half a measure.
 

IV. The rationale of "since it could be joined" as an indication, and the status of half a measure according to the position of Rabbi Yochanan

 
            In any event the rationale of "since it could be joined" is an important element in the position of Rabbi Yochanan and it requires explanation. In my opinion, the simple understanding is that this rationale serves as an "indication." That is to say, the fact that the action that was performed could be joined to another in order to reach a full measure that carries liability teaches us that even that which was already performed is of a sufficiently negative character to be defined as forbidden by Torah law. We must, however, understand how this fits in with Resh Lakish's assertion that there is no eating with less than the size of an olive. Two options stand before us:
 
1. It may be argued that Rabbi Yochanan disagrees with Resh Lakish's assertion, based on the rationale of "since it could be joined." That is to say, Rabbi Yochanan maintains that since the eating of a ke-zayit is comprised of eating parts of a ke-zayit, it is reasonable to assume that even the eating of those parts are defined as a process of eating, and that the eating of a full ke-zayit is defined as a sufficiently significant quantity in order to impose liability. But even the eating of a part of that amount is regarded as eating, and does not constitute a phenomenon that by its very definition is distinct from the eating of the entire quantity. The Mishneh le-Melekh (Hilkhot Chametz u-Matza 1:7) cites such an argument in the name of the Mizrachi (and disagrees with it).
 
2. The words of the Rashba in his Responsa indicate that Rabbi Yochanan accepts Resh Lakish's fundamental assertion that there is no eating with less than the size of an olive, but he maintains that there is, nevertheless, room for a Torah prohibition at a partial level even if there is no act of eating:
 
You asked further: What is the reason that half a measure is forbidden by Torah law, and yet there are no lashes? If it is forbidden, we are bound by a negative prohibition not to eat it! The answer is: There are no lashes, because the fundamental verse mentions "eating":  "You shall not eat anything that dies of itself," You shall not eat any fat or blood," and there is no eating less than the size of an olive. However, since it says "any" (kol) and it doesn't say: "You shall not eat that which dies of itself," or "You shall not eat fat or blood," the verse teaches us that even if there is no measure, you shall not eat it. And after the inclusion, there is an exclusion. What is the inclusion? For the prohibition. And what is the exclusion? For lashes. (Responsa ha-Rashba, I, no. 439)
 
The Rashba bases his remarks on the fact that the prohibition of half a measure is derived from the inclusion implied by the word kol, "any." However, there might be room to base this also on the rationale of "since it could be joined," by saying that this is not a sign that we are dealing with an act of eating, but rather that there is a prohibition even if there is no such action. Since we are dealing with a substance that if we join it with more of the same substance so that it reaches the minimal measure, there would be liability for the full transgression of a Torah prohibition, this is a sign that this substance is negative, and therefore we must not consume of it even if there is no act of eating. It may be added that Rabbi Yochanan may accept the assertion that "the Torah speaks of eating and this is not [eating]," but he maintains that even though the prohibition that the Torah imposes on a person is one of eating, we nevertheless understand that the object of the prohibition is negative, and that it may not be eaten even if there is no prohibition on the person to do so. Later in our study we will see the positions of Rishonim according to which half a measure is forbidden by Torah law, but the person is not "committed to the oath from Mount Sinai on" (and not because there is no punishment, for a prohibition that stems from a positive commandment (issur aseh) falls into the category of "committed to the oath from Mount Sinai," even though there is no punishment). It may be that this is based on what we have proposed, that we are dealing with a Torah prohibition, but not with a prohibition imposed upon the person.
 

V. The rationale of "since it could be joined" as the reason for the prohibition of Half a measure

 
            As I have suggested, it is reasonable to understand the rationale of "since it could be joined" as a sign that even that which was already performed is problematic, and this was my assumption in the two explanations that we have already seen. There are, however, those who understood that we are dealing with the reason for the prohibition, that is to say, that even though there is no problem with eating half a measure, there is room to forbid it because if the eater continues with his behavior, he will transgress a full-fledged Torah prohibition. This might be sort of a precautionary measure imposed by Torah law that was meant to distance a person from the prohibition. This seems to explain the surprising position, according to which there is no Torah prohibition to eat half a measure of chametz at the last minute of Pesach or to eat half a measure of food at the last minute of Yom Kippur, were it not for a special derivation:
 
At the beginning of the last chapter of Yoma it is explained that the reason that Rabbi Yochanan says that a half measure is forbidden by Torah law is "since it could be joined." According to this, in the case of a prohibition that is time bound, e.g., chametz on Pesach, where he ate less that a measure on the seventh day, in such a way that there was no time left to eat any more [on the seventh day] in order to complete the measure, this cannot be derived from "any fat," and therefore the Rambam derives it from "You shall not eat" (Tzelach, Pesachim 44a).
 
As I have said, I am not inclined to accept this understanding, but it is possible that in the continuation of our study we will see that it has a foundation in the words of the Rishonim.
 

VI. Half a measure – a general prohibition or a branch of each specific prohibition

 
An interesting question concerning the prohibition of half a measure rises in the words of the Ramban in his Torat ha-Adam (Sha'ar ha-Michush – Inyan ha-Sakana). The Ramban deals there with a sick person who is in mortal danger, and is therefore permitted to eat food that is otherwise prohibited, because of the threat to his life, with two limitations: 1. If he can suffice with half a measure, he must do so; 2. If possible, he should be given food the prohibition of which is the least severe, e.g., he should be given to eat nevela, meat from an animal that was not properly slaughtered, which is forbidden by an ordinary prohibition and therefore punishable by lashes, rather than forbidden fat, which is punishable by excision. The Ramban raises the question: If we are dealing with eating less than a measure, then in all cases we are dealing with a "mere prohibition," as he puts it, which does not carry liability for lashes or for excision, so what is the extra severity of the one over the other? In his second answer the Ramban writes that the law of giving food the prohibition of which is the least severe applies only to one who must eat a full measure. Only in his first answer does he suggest: "Since when eaten in the full measure, the one prohibition is more severe than the other with respect to their punishments, so too when eaten in less than the full measure, the severity of the one prohibition is greater than that of the other." The prohibition of half a measure is not a general concept but rather a partial level of each specific prohibition. How are we to understand the Ramban's approach in his question and in his second answer, from which it follows that the prohibition of half a measure is a general prohibition, and that there is no difference in severity between half a measure of a prohibition that is punishable by lashes and half a measure of a prohibition that is punishable by excision?[3] According to the approach that we are dealing with sort of a precautionary measure by Torah law that rests on the possibility of violating the full prohibition, it may be that it is a general precautionary measure that does not depend on the specific prohibition. It may also be argued that even if the prohibition of half a measure is indeed a branch of each specific prohibition, there is no greater stringency with a half measure of forbidden fat than with a half measure of pig, because the difference between them relates to the level of the sanction, and not to the very fact that we are dealing with a forbidden material the consumption of which is negative, which is what is significant with respect to half a measure.
 

VII. Half a measure with regard to prohibitions that are not prohibitions of eating 

 
According to the way that we have read the Gemara in Yoma, it would appear that the dispute between Rabbi Yochanan and Resh Lakish relates exclusively to prohibitions of eating. As I have suggested, it is possible that there is room for something to be forbidden even without the minimal measure for liability, only that according to Resh Lakish in the context of eating, the eating that is prohibited by the Torah is only met with the eating of a ke-zayit, whereas Rabbi Yochanan deals with this argument in one way or another. In light of this, it is possible that in the case of other Torah prohibitions half a measure should be forbidden by Torah law even according to Resh Lakish. This would be true unless we find that the relevant measure in the particular prohibition defines the essence of the prohibition or forbidden action, in which case it stands to reason that half a measure should be permitted, at least by Torah law, even according to Rabbi Yochanan. 
 
It may, however, be argued that if Rabbi Yochanan's position is based on "since it could be joined" as the reason for the prohibition, it should apply whenever a partial action could be joined with another partial action to form a complete prohibition (e.g., a Nazirite who shaves a single hair). So too, if Rabbi Yochanan's position is based on the Scriptural decree from the words "any fat," there is room to say that this applies to all prohibitions in the Torah (though there are those who say that this relates exclusively to prohibitions of eating; see Responsa Chakham Tzvi, no. 86). It may also be possible to argue that the dispute between Rabbi Yochanan and Resh Lakish is about the more general question whether or not quantity defines the essence of an action, but this seems difficult to me.
 
In any event, there are those who explicitly say that the law of half a measure relates only to prohibitions of eating (see, for example, the aforementioned responsum of the Chakham Tzvi, who suggested this for additional reasons as well); but in practice we find discussions about half a measure regarding other prohibitions as well, and relating this question to the disagreement between Rabbi Yochanan and Resh Lakish:
 
1. The context of the dispute in Yoma relates to eating on Yom Kippur. This is indeed a case of eating, but ostensibly we are not dealing with an act of eating that is defined among other ways by the measure of a ke-zayit, but rather by the eating the larger measure of a date (see Yerushalmi, Terumot 6:1, which appears to have detached the laws of Yom Kippur from the Amoraic dispute).
 
2. Rashi, in Shabbat, writes with respect to the labors that are forbidden on Shabbat: "Is it permissible to bake less than the minimal measure? Even if there is no liability for a sin-offering, there is nevertheless a prohibition, for we say that half a measure is forbidden by Torah law, in the last chapter of Yoma (74a).[4]
 
As stated, this is not a simple matter, and further study is required, but since we will encounter the law of half a measure regarding other prohibitions that do not involve eating, I thought it appropriate to deal with this issue as well.
 
(Translated by David Strauss)
 
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Sources for the next shiur: The Dispute Between Rabbi Akiva and the Sages - One who takes an oath that he will not eat, and he eats less than the size of an olive (Part I)
 
19b in the Mishna; 21b: "Shevu'a shelo okhal… shema mina"; 21b, Tosafot, s.v. heikhan matzinu be-okhel, heikhan matzina be-medaber; Rashi, 19b, s.v. be-medaber; Ri Migash 21b, s.v. matnitin (below); Mishneh le-Melekh, Hilkhot Shevu'ot 4:1, "Ve-da de-be-resh perek gimmel de-Shevuot… ve-divrei ha-Re'em tzerikhin talmud"; Yerushalmi, Shevuot 3:1, "Ma nan kayamin im be-omer… al da'ateih de-Rabbanan asurin."
 
Ri Migash:
Mishna: "I swear I shall not eat," and he ate a minute quantity, he is liable; these are the words of Rabbi Akiva. They [the Sages] said to Rabbi Akiva: Where do we find that he who eats a minute quantity is liable – This means: Regarding all prohibited foods in the Torah, one who eats them is only liable if he eats of them the size of an olive. And this person, once he swears about this loaf that he will not eat it, it becomes forbidden to him. This being the case, why should he become liable for it for a minute amount? He said to them: But where do we find that he who speaks brings an offering, that this one should bring an offering?
 
 
 

[1] Chazon Ish, Choshen Mishpat, Likkutim, no. 23, on Makkot 17a.
[2] One brings a sacrifice (chatat) for the inadvertant transgression of those prohibitions whose punishment for deliberate transgression is excision (karet).
[3] The sting of this question is lessened if we accept the approach according to which the law that a person who must be fed a prohibited food for pikuach nefesh should be given food the prohibition of which is least severe, is a rabbinic law (see Kiryat Sefer, Hilkhot Ma'akhalot Asurot 14), in which case it may be argued that this stringency only applies to one who eats a full measure.
[4] His grandson, the Rashbam (in his commentary to Bava Batra 55b) writes that performing a melakha on Shabbat, less than the minimal measure, is not prohibited by Torah law, but this is on account of a consideration that is specific to the laws of Shabbat: "In tractate Shabbat we learned: "One who takes food out [from a private to a public domain] is liable for the size of a dried fig; for regarding Shabbat, the Torah prohibited creative work, and less than the size of a dried fig is not considered a significant act of taking out [from one domain to another]."