1) OVERRIDING A "SHIBUD" WITH A "NEDER"
QUESTION: The Mishnah states that a man may prohibit his wife with a Neder from deriving any pleasure from him, and as a result he becomes unable to provide his wife with Mezonos, financial support. The Mishnah says that he nevertheless may appoint a "Parnas" (benefactor) to support his wife.
The Gemara asks that the husband should not be able to prohibit himself with a Neder from providing his wife with Mezonos since he is obligated by the Torah to provide her with Mezonos and he is not entitled to remove that obligation.
The Gemara gives a number of answers. In one answer, the Gemara says that the Mishnah refers to a case in which the husband made the Neder during Erusin and prohibited his Arusah from deriving any pleasure from him. The Mishnah earlier (57a) teaches that an Arusah is entitled to receive Mezonos after twelve months have passed. The Mishnah here teaches that the husband's Neder can override his obligation to provide the Arusah with Mezonos after twelve months.
RASHI explains why the husband's Neder is able to override the obligation to give Mezonos to his Arusah after twelve months. He explains that during Erusin, the obligation to support her is only mid'Rabanan. Since a Neder takes effect mid'Oraisa, it overrides the obligation mid'Rabanan to give Mezonos to the Arusah. Rashi implies that after Nisu'in the obligation to feed one's wife is mid'Oraisa, and that is why a Neder cannot override his obligation to give her Mezonos after Nisu'in.
Rashi's explanation is difficult to understand.
(a) The Gemara earlier (47b) cites an opinion that the obligation to provide Mezonos to a Nesu'ah is only mid'Rabanan. Many Rishonim rule in accordance with this opinion because Rav Huna in the name of Rav (58b) follows this opinion when he rules that a woman is entitled to say, "Eini Nizones v'Eini Osah" -- "I decline the right to receive the Mezonos [from my husband] in order not to have to give him my Ma'aseh Yadayim," and the Halachah follows Rav Huna's ruling. According to Rashi, however -- who maintains that whenever a Neder is made against a Chiyuv d'Rabanan the Neder (which is d'Oraisa) overrides the Chiyuv d'Rabanan -- even after the Nisu'in the husband should be able to prohibit himself with a Neder from feeding his wife because the Chiyuv of Mezonos even for a Nesu'ah is only mid'Rabanan!
(b) The Gemara (70a) says that if a woman makes a Neder to prohibit to her husband anything she produces, the Neder does not take effect because of the Shibud (obligation) which requires her to give her Ma'aseh Yadayim to her husband. However, this Shibud of the woman to her husband certainly is only mid'Rabanan. Why, then, should a Neder d'Oraisa not be able to override it?
(c) The Gemara earlier (59b) teaches that Hekdesh and Konamos (Neder) override a Shibud. As Rashi explains, if a person designated an object as a lien ("Apotiki") for the repayment of a loan, and then he made that object Hekdesh, the Shibud to the creditor is removed and there is no longer a lien on that object for the loan. According to Rashi here who says that a Neder cannot override an obligation that is mid'Oraisa, Hekdesh also should not be able to override a Shibud d'Oraisa because the Gemara there compares the two! Why, then, should Hekdesh be able to override a lien for a debt? The lien is a Chiyuv d'Oraisa since he specifically designated it as a lien for the debt!
(d) TOSFOS suggests a simpler explanation for the Gemara. When the Gemara mentions that the husband is obligated to support his wife after twelve months of Erusin have passed, it refers to a case in which the husband made the Neder before twelve months passed. Once twelve months have passed, the Neder takes effect to exempt him from paying Mezonos because the Neder preceded his obligation of Mezonos. This is the same logic which the Gemara suggests in the answer that follows, when it says that a man can prohibit his wife from deriving pleasure from him when he makes the Neder while she is an Arusah and then he marries her and makes her a Nesu'ah. Since the Neder preceded the marriage and the obligations of the marriage, it can override those obligations. The only reason why the Gemara rejects this answer is that in such a case when the woman agrees to get married she accepts upon herself that she is also not going to receive Mezonos, as she enters the marriage willingly. When the date marking twelve months arrives, however, the woman did nothing to imply that she is ready to lose the Mezonos. Therefore, she should not lose the Mezonos, and the husband's Neder remains in force (and he must appoint a Parnas).
Tosfos' explanation seems to be the most straightforward way of explaining the Gemara. Why does Rashi not explain that way?
ANSWERS:
(a) Rashi seems to have a different approach (from that of the other Rishonim) to how a Neder overrides a Shibud. The source for what Rashi says -- that a Neder (Konam) overrides an obligation only when the obligation is d'Rabanan -- is apparently the Gemara earlier (59b) which asks why a woman cannot prohibit her Ma'aseh Yadayim to her husband if a Neder usually overrides a Shibud. The Gemara there answers that the Rabanan strengthened the Shibud that a husband is entitled to receive from his wife. Rashi explains that this means that the husband is considered more than just a creditor to the wife, someone to whom the wife owes money. He is considered a buyer, and what she produces is considered actually sold to him.
This concept -- that the husband is considered to have bought the various items of his wife to which he is entitled -- is expressed by Rashi elsewhere (50a, DH ha'Ba'al). However, the converse is never found -- that what the wife is entitled to receive from the husband is considered to have been purchased from him. Why, then, does the Gemara assume in many places that the man cannot prohibit himself from giving her the Mezonos or the other Shibudim which obligate him, such as the obligation of Onah (Rashi 61b, DH ha'Madir, see Insights there)? He should be able to prohibit those things to his wife!
Because of this question, Rashi understands that a Neder only overrides a Shibud that is mid'Rabanan, such as the Shibud that a woman has to her husband (if not for the fact that the Rabanan strengthened that Shibud). A Neder cannot override the Shibudim which a man has to his wife because his Shibudim (to provide her with Mezonos and Onah) are mid'Oraisa. The Gemaras which say that he cannot make a Neder to override his obligation to provide her with Mezonos maintain that Mezonos is a Chiyuv d'Oraisa (like the opinion of the Tana on 47b).
The RASHBA points out that if Rashi here rules that the obligation to provide Mezonos is mid'Oraisa, he is in agreement with the RAMBAM (Hilchos Ishus 12:2) who rules this way as well. The Rashba explains that according to Rashi and the Rambam, it is possible that a woman may still say "Eini Nizones v'Eini Osah" and exempt her husband from giving her Mezonos and keep her Ma'aseh Yadayim to herself, because the Rabanan removed his Chiyuv mid'Oraisa of Mezonos in such a case.
(b) The reason why the wife cannot prohibit her Ma'aseh Yadayim to her husband even though it is only a Shibud d'Rabanan is that the Rabanan strengthened the Shibud that a woman has to her husband, as the Gemara says earlier (59b). (RASHBA)
(c) RAV Y. S. ELYASHIV shlit'a (as cited in HE'OROS B'MASECHES KESUVOS) explains that Rashi may understand that when the Gemara says that a Neder overrides a Shibud, it follows the opinion that all Shibudim are mid'Rabanan. Even when a person designates a certain object as a lien for a loan, he cannot create a Shibud mid'Oraisa according to the opinion that all Shibudim are mid'Rabanan. (This is in contrast to the view of the RITVA in Kidushin 14b, who writes that when one specifies that an object is to be used as a lien, it is indeed a Shibud d'Oraisa according to all opinions.)
(d) Why does Rashi not give the same explanation as Tosfos, that the husband made the Neder and removed the Shibud before the twelve months arrived? Rashi may understand that since the husband accepted upon himself the obligation to support the woman after twelve months of Erusin, the Shibud to support her preceded the Neder, even though the actual payments do not precede the Neder. Therefore, this case is not comparable to the man who prohibits his wife before Nisu'in, since before Nisu'in he never accepted upon himself any of the Shibudim of Nisu'in. (M. KORNFELD)

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