1) THE FORBIDDEN ELEMENT OF AN "ISUR HANA'AH"
OPINIONS: The Mishnah (14b) states that if a man's wife tells him that she has become a Nidah while they are having relations, and he separates from her immediately, he is Chayav, because by separating from her he had pleasure. Rather, he must wait until he will no longer derive pleasure from separating from her, and then he must separate from her. The Gemara here quotes Rava who derives from this law that a man who is "Meshamesh Mes" with a woman who is forbidden to him is not Chayav, since he derives no pleasure.
Does this Gemara imply that in a case of an Isur Hana'ah, the prohibition is the pleasure that is derived ("Hana'as Be'ilah"), and not the act that is performed ("Ma'aseh Be'ilah")?
(a) The ASVUN D'ORAISA (#24) proves from this Gemara that such Isurim are, by definition, "prohibitions of pleasure," and not Isurim of prohibited actions. He points out that the Gemara emphasizes that in the case of the Mishnah, the man has transgressed because he derived pleasure.
He proves this further from the Gemara in Chulin (115b), which teaches Rebbi's opinion of how the Torah teaches that one may not derive pleasure from a mixture of meat and milk. Rebbi says that there is a Gezeirah Shavah which teaches that just as there is pleasure in the sin of a Kadesh, deriving pleasure from a mixture of meat and milk is also forbidden. If, in the case of a Kadesh, the Torah prohibits the act itself and not the pleasure per se, then how can Rebbi derive from there that deriving pleasure from a mixture of meat and milk is prohibited? The Torah does not mention that the pleasure is forbidden!
The OR SAME'ACH (Hilchos Ma'achalos Asuros 14) agrees in part with this approach, but he adds that there is a difference between the Isurim of forbidden relations and the Isurim of forbidden foods. In Isurim of forbidden relations, there is no "amount" which is forbidden. Therefore, it is logical to assume that the Torah prohibits the actual pleasure, as the Gemara here says. Isurim of forbidden foods, in contrast, are of a different nature. The Torah established amounts (such as a k'Zayis, k'Beitzah, etc.) of forbidden food for which one transgresses the prohibition. This indicates that the physical amounts are of consequence, and not the amount of pleasure.
(b) The KEHILOS YAKOV (Kidushin #40) disagrees with the premise of the Asvun d'Oraisa. The Torah forbids actions, not pleasure. Prohibitions against eating certain items are prohibitions against performing acts of eating, not of deriving pleasure. He rejects the proofs of the Asvun d'Oraisa and explains that the Gemara here means that since the pleasure of separating from relations is similar to the pleasure of having relations, it is considered an action of having relations, and it is that action which is forbidden (and not the pleasure derived therefrom). The Kehilos Yakov further asserts that the Gemara in Chulin is no proof, since the Gemara can use a Gezeirah Shavah to take a normal characteristic of a prohibition and teach another similar prohibition.
The Kehilos Yakov admits, however, that the Gemara here poses a problem to his approach. The Gemara quotes Rava who states that one who is "Meshamesh Mes" with a woman who is forbidden to him does not transgress the Isur of forbidden relations. Abaye argues and says that Rava's inference from the Mishnah is incorrect. A person normally is Chayav for an act of "Meshamesh Mes." The Mishnah is discussing a person who was notified of the Isur only while in the midst of the act. Such a person is considered a victim of circumstance and is not guilty when he separates "b'Ever Mes." The Gemara asks that if the reason for his innocence is that he is a victim of circumstance, then even when he separates immediately he should be innocent! The Gemara answers that since he could have separated with only a small amount of pleasure and he chose to separate with an increased amount of pleasure, he is guilty. This implies that according to Abaye, the pleasure itself is what is prohibited, because if the action is what is prohibited, then the man should be innocent in both cases, since he had to cease the prohibited action in whatever way he could.
The Kehilos Yakov answers this question based on the words of the ROSH in Yevamos (6:2). The Rosh writes that a man is required to allow himself to be killed rather than transgress an Isur of forbidden relations. Although he is not considered to be transgressing the Isur when he remains passive, the Gemara attests that a man is never considered passive in an act of relations, since he is physically able to have relations only if he has intention to do so. The Rosh asks how this principle is consistent with Abaye's statement. If one who is a "Meshamesh Mes" is guilty, then the Gemara there does not need to say that the man's involvement is always active; even if he is passive, he still derives pleasure and is guilty according to Abaye!
The Rosh answers that the Gemara in Yevamos follows the view of Rava as expressed here in Shevuos, who maintains that "Meshamesh Mes" is not a transgression. Moreover, even according to Abaye, when a man increases his pleasure by becoming physically able to have relations, his action is considered as though it was done intentionally in its entirety. This is like Abaye's own answer here in Shevuos, when he says that the man is guilty because he should have separated with less pleasure.
The Kehilos Yakov explains that his question was incorrect, according to the words of the Rosh. While it is true that the man was forced to separate in one way or another, by separating with more pleasure he removed himself from the status of being a victim of circumstance, and instead categorized himself as one who did the act willingly. This means that even according to Abaye, the man's choice of the more pleasurable way to separate categorizes him as one who knowingly transgressed an Isur with an action. Accordingly, it still stands to reason that the action of the sin is forbidden, and not the pleasure.
A practical consequence of these two approaches -- whether the action itself is prohibited or whether the pleasure is prohibited -- exists in a case in which a person is forced, due to circumstances (such as Piku'ach Nefesh), to transgress an Isur (such as to eat non-kosher meat). If the action is what is prohibited, then perhaps the person may eat the choicest, tastiest meat, since he is permitted to do the action in this circumstance. If, however, the pleasure is what is prohibited, then perhaps he may not eat the choicest, tastiest meat, but rather he may eat only meat of lesser quality, because he must minimize the pleasure that he receives, since it is the pleasure which is forbidden. (Y. MONTROSE)

18b----------------------------------------18b

2) HALACHAH: THE NATURE OF THE PROHIBITION OF "SAMUCH LA'VESTAH"
OPINIONS: The Gemara records a Beraisa in which Rebbi Yoshiyah teaches that the Torah requires a man to separate from his wife when she is "Samuch la'Vestah," when she nears the time that she expects to become a Nidah. He learns this from the verse, "You shall separate the people of Israel from their Tum'ah" (Vayikra 15:31)."
Is this a Torah prohibition, or is it a rabbinical prohibition which uses the verse as an Asmachta?
(a) The RASHBA and RITVA in Yevamos (62b) explain that the prohibition against being with one's wife when she is "Samuch la'Vestah" is mid'Rabanan. This view is supported by the Gemara in Yevamos, which says that a man is obligated to be with his wife before he departs on a trip, even if it happens to be "Samuch la'Vestah." If the Isur of "Samuch la'Vestah" is mid'Oraisa, the Rabanan would not have instituted such an obligation. If the Isur is mid'Rabanan, then it is clear that the Rabanan have the right to override their own enactment when they see fit to do so.
The Ritva here in Shevuos, however, refutes the proof from the Gemara in Yevamos. Even if the prohibition against being with one's wife when she is "Samuch la'Vestah" is mid'Oraisa, the Torah itself permits a man to be with his wife immediately before he departs on a trip, even when it is "Samuch la'Vestah." This is derived from the end of the verse quoted in the Gemara in Yevamos, "And you shall visit your residence and you will not sin" (Iyov 5:24). The verse concludes with the words "and you will not sin" because it is assuring the man that since he is fulfilling his obligation to be with his wife for the purpose of a Mitzvah, his wife will not become a Nidah at that moment even though she is "Samuch la'Vestah." (See Insights to Yevamos 62:2.)
The RAN, RASHBA, and other Rishonim give another proof that the Isur of "Samuch la'Vestah" is mid'Rabanan. The Gemara in Nidah (15a) records a dispute about whether the Isur during the woman's Veses is mid'Oraisa or mid'Rabanan. These Rishonim rule that the Isur during the Veses itself is only mid'Rabanan. According to this opinion, it is obvious that "Samuch la'Vestah" must also be mid'Rabanan.
(b) Other Rishonim explain the Gemara in Nidah differently. They explain that the dispute in Nidah is not about a woman's prohibition during her Veses. Rather, the dispute involves merely the woman's status after her Veses has passed and she has not yet determined her status. Everyone agrees that during her Veses, the Torah forbids her to have relations. According to this interpretation, there is no reason why "Samuch la'Vestah" cannot be a Torah prohibition.
The NODA B'YEHUDAH (YD 1:55) cites proof for this view from the Gemara in Gitin (28b). The Gemara there rules that when relevant, the Halachah takes into account, in cases of doubt, the possibility that a person might die, but the Halachah does not suspect that a person has already died. What is the logic behind this difference? The difference lies in the Chazakah (status quo) of the person. If a person has a Chazakah that he is alive, then the Halachah does not suspect, out of doubt, that he might have already died, since that would be counter to his Chazakah. On the other hand, if there is a concern that someone might die due to circumstances, the Halachah may suspect that he will die; this does not contradict his status quo that says that until now he was alive, since the doubt is whether he will die in the near future.
The Noda b'Yehudah explains that according to the Gemara in Gitin, the prohibition during a woman's Veses is a relatively weak prohibition (according to the opinion that it is mid'Rabanan), because once a woman passes her Veses without becoming a Nidah, it makes sense that she retains her previous status of Tehorah. The Halachah does not suspect that she became a Nidah and did not know it, just as the Halachah does not suspect that someone died, since such a suspicion would be counter to the person's Chazakah (status quo). Therefore, the Torah does not forbid the time of the actual Veses. However, at the time immediately before she expects to become a Nidah, there is concern that she is about to become a Nidah. Hence, it is possible that the opinion that the Isur of Veses is mid'Rabanan may agree that "Samuch la'Vestah" is forbidden by the Torah. This is also the approach of the CHASAM SOFER (Teshuvos YD 170, 179).
(The ARUCH HA'SHULCHAN (YD 184) adds that this is the approach of many Rishonim. He cites the RAMBAM who rules that the Isur of Veses is mid'Rabanan, but when the Rambam writes that "Samuch la'Vestah" is forbidden he makes no mention that it is mid'Rabanan. The Aruch ha'Shulchan asserts that the Rambam almost always mentions when an Isur is mid'Rabanan if that is the case. The Rambam's omission here indicates that "Samuch la'Vestah" is forbidden mid'Oraisa. The Aruch ha'Shulchan adds that this is also the proper way of understanding TOSFOS in Yevamos (62b) and the ROSH.)
Although the Aruch ha'Shulchan and others agree that "Samuch la'Vestah" is forbidden mid'Oraisa even though the Isur of Veses is mid'Rabanan, they disagree with the proof cited by the Noda b'Yehudah. The Aruch ha'Shulchan says that the case of Veses is not comparable to the case in Gitin. In the case in Gitin, the threat of death constantly looms over the person, and therefore the possibility of his death is a very real concern. In contrast, a woman is not inevitably going to have a flow of Dam; there are many factors (such as pregnancy, or illness) that may prevent her from becoming a Nidah at any future time.
The Aruch ha'Shulchan instead suggests a different argument to explain why "Samuch la'Vestah" is Asur mid'Oraisa even though Veses itself is Asur mid'Rabanan. He explains that, in contrast to the assumption of the Noda b'Yehudah, there is no Chazakah at all that a woman who was Tehorah in the past is still Tehorah. The nature of a woman is to constantly change from the status of Tehorah to the status of Teme'ah. Under such circumstances, no Chazakah can be established. This is known as "Chazakah ha'Asuyah l'Hishtanos."
According to this approach, why does the verse need to warn men to separate from their wives "Samuch la'Vestah"? Even without the verse, they should be prohibited from being with their wives, since the woman is expected to become a Nidah and has no Chezkas Taharah!
The CHAZON ISH (YD 80:8) explains that although the verse indeed is not needed to teach that a man must separate from his wife at the time of "Samuch la'Vestah," the verse is needed to teach that if he had relations "Samuch la'Vestah," he is considered a sinner even if his wife does not become a Nidah at that time.
(This discussion applies only to the requirement to separate, at "Samuch la'Vestah," from a woman who has a Veses Kavu'a, a set time at which she becomes a Nidah each month. The requirement to separate from a woman who has a Veses which is not Kavu'a (the category into which most women fall nowadays) is only mid'Rabanan according to all opinions.) (Y. MONTROSE)

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