1) PROOF THAT DIVORCE IS LIKE "HAKAMAH"
QUESTION: The Gemara attempts to prove from a Beraisa that Gerushin, divorce, constitutes Hakamah. The Beraisa lists the cases in which "Nisroknah" applies, but it does not include the case of "Shama ha'Arus v'Giresh Bo ba'Yom" -- "the Arus heard the Neder and divorced her on the same day." It must be that Gerushin is considered like Hakamah and therefore "Nisroknah" does not apply.
The Gemara rejects this proof. The end of the same Beraisa lists the cases in which "Nisroknah" does not apply (because the Arus upheld the Neder in some way) and yet it does not include the case of "Giresh ha'Arus" -- "the husband divorced her" -- as one of the examples of Hakamah. Accordingly, no inference may be made from the Beraisa with regard to Gerushin. Rather, the Beraisa omits the case of Gerushin so that the wording of the first half of the Beraisa and the second half of the Beraisa will be parallel.
The RAN explains that even if Gerushin is not like Hakamah, the Beraisa does not list Gerushin among the cases of the Reisha because it could not list a diametrically contrasting case in the Seifa, as there is nothing parallel to Gerushin which constitutes a Hakamah.
REBBI AKIVA EIGER (in Gilyon ha'Shas) asks that the Ran's intention is difficult to understand. The first half of the Beraisa lists cases in which there is no Hakamah. One of those cases is where an Arus heard the Neder and died that day. The second half of the Beraisa lists the diametrically contrasting case of an Arus who was silent when he heard the Neder and died the next day; his silence was a Hakamah of the Neder. Why does the Beraisa not use the same type of contrast with regard to a case of Gerushin? The first half of the Beraisa could have listed the case of an Arus who heard the Neder and then divorced the Arusah on the same day (in which case the Gerushin would not constitute Hakamah), and the second half of the Beraisa could have contrasted that case with the case of an Arus who heard the Neder and divorced her on the next day (in which case the Gerushin would constitute Hakamah)! (See RASHASH.)
ANSWER: Each case in the Seifa which contrasts the corresponding case in the Reisha must contrast the element of the case in the Reisha which precludes the efficacy of the Hakamah. In the case of the Arus who died that day, the reason his silence on the day he heard the Neder is not Hakamah is that he was silent for only part of the day (because he died before the end of the day arrived). The Seifa therefore contrasts this case by saying that if he was silent the entire day, his silence is a Hakamah. This case directly contrasts the case in the Reisha, in which his silence is not considered a Hakamah.
If the Reisha would mention the case of an Arus who divorced his wife on the same day he heard the Neder, it would teach that it is the Gerushin itself that does not constitute Hakamah. The Seifa would have to contrast that case with something similar to Gerushin which does constitute Hakamah even when it is done on the same day. Such a case would be the case of an Arus who heard the Neder and divorced his wife the next day, but that case does not contrast the element of Gerushin that precludes Hakamah in the case of the Reisha. The reason why there would be Hakamah in that case is not because the Gerushin is a Hakamah, but because the silence on the day he heard the Neder is a Hakamah.
Perhaps Rebbi Akiva Eiger does not accept this approach because the Reisha mentions a case of "Shama v'Hefer" (the Arus heard the Neder and annulled it) and the Seifa contrasts it with a case of "Shama v'Hekem" (the Arus heard the Neder and upheld it). How is Hakamah a similar act to Hafarah such that it contrasts the element in Hafarah which precludes the Hakamah? They are two completely different acts! Since the Beraisa contrasts such cases, it also could have contrasted the case of Gerushin on the day of the Neder with the case of Gerushin the day after the Neder.
Perhaps the Ran is consistent with his own view that the husband's silence on the day he hears the Neder constitutes Hakamah, since the day passed with no Hafarah from the husband (see Insights to 69:1). According to the Ran, an act Hafarah would prevent the Hakamah which silence constitutes by creating a protest to the Neder before the day passed. Therefore, it is appropriate to call Hakamah the opposite of Hafarah, in the sense that the husband either upheld the Neder explicitly or let the day pass without saying anything.
2) PROOF THAT DIVORCE IS NOT LIKE "HAKAMAH"
QUESTION: The Gemara attempts to prove from the Mishnah (71a) that Gerushin does not constitute Hakamah. The Mishnah states that when an Arus divorces his wife after she made her Neder, and she becomes betrothed to a second Arus on the same day, the second Arus -- together with her father -- may annul her Neder. The Mishnah's addition of the condition that the second Arus may annul her Neder only if she became betrothed to him on the same day that the first Arus divorced her shows that either the father or the first Arus indeed heard her Neder before the divorce.
The Gemara infers that since the Mishnah means that the Arus heard the Neder before he divorced her and nevertheless the second Arus may annul the Neder, it must be that Gerushin is not considered Hakamah, because otherwise the second Arus would not be able to annul the Neder.
The Gemara rejects this proof and says that the Mishnah does not mean that the Arus heard the Neder before he divorced her, but it means that the father heard the Neder. Since the Arus did not hear the Neder, his Gerushin cannot constitute Hakamah in this case. The Mishnah means that if the father heard the Neder before the Arus divorced her and then she became betrothed the same day to someone else, the father and the second Arus may annul the Neder together. When, however, the first Arus heard the Neder before the divorce, perhaps indeed the Gerushin is considered like Hakamah.
According to the Gemara's explanation of the Mishnah, what is the Mishnah's intention when it says that the second Arus may annul the Neder only when he marries her on the same day? The Mishnah cannot be teaching that Hafarah may be done only on "Yom Sham'o," and thus if the father heard the Neder on that day he must annul it on that day, because It is obvious that the father's Hafarah with the second Arus is valid only on the day he (the father) heard the Neder! Why would one have thought that the second betrothal changes the father's requirement of "Yom Sham'o"?
The Mishnah should have discussed a case in which neither the father nor the first Arus heard the Neder, in which case the second Arus may annul the Neder with the father even when the second betrothal takes place on another day.
Even if the Mishnah chooses to discuss a case in which the father heard the Neder, it should teach that the second Arus may annul the Neder after a number of days as long as the father not only heard the Neder while the first Arus was still married but also annulled the Neder at that time. Since he already annulled his share of the Neder, whether his daughter marries the second Arus on "Yom Sham'o" or on another day is immaterial; the second Arus may still annul his portion of the Neder.
On the other hand, according to the Gemara's original assumption that the first Arus heard the Neder, the Mishnah teaches a Chidush that Gerushin does not constitute Hakamah. What, though, is the Mishnah teaching according to the Gemara's rejection of its initial way of understanding the Mishnah?
ANSWERS:
(a) According to TOSFOS (cited by the Ran, 71b), Beis Hillel maintains that the second Arus cannot annul the Neder when the father annulled the Neder before the first Arus died (because the Neder is now too weak to pass on to the second Arus). This is the intention of the Mishnah. When the father heard the Neder (but did not do Hafarah), the second Arus cannot do Hafarah unless he became betrothed to the Na'arah on that day. When the father did Hafarah before the first Arus divorced her, the second Arus cannot do Hafarah at all (and if the father heard the Neder before the divorce but did not do Hafarah before the divorce, the father cannot do Hafarah when the second Arus marries her unless he marries her on the same day). The Mishnah teaches the Chidush expressed by Tosfos, that the second Arus cannot do Hafarah if the father did Hafarah before the first Arus divorced her. The father's Hafarah weakens the Neder such that it cannot be passed from the first Arus to the second Arus.
(b) The RAN, however, does not agree with the assertion of Tosfos. According to the Ran, what is the Mishnah teaching?
The answer is that the Ran follows his own view as expressed elsewhere (69a), where he writes that the Hafarah of one of the partners becomes void if the other partner was unable to do Hafarah for any period of time (see Insights to 71:1). The Mishnah teaches that when the father heard the Neder, he must do Hafarah a second time with the second Arus even if he already did Hafarah before the first Arus divorced her, because there was a moment (i.e. after the divorce) during which he could not do Hafarah (according to Beis Hillel). This is what the Mishnah intends to teach when it says that the father and second Arus are able to annul her Neder only when she becomes betrothed again on the same day.
(c) The RAMBAM (Hilchos Nedarim 12:17) infers from the verses in the Parshah of Hafarah that the Arus and the father must do Hafarah together on the same day. (Most Rishonim disagree and rule that each one may do Hafarah on the day on which he hears the Neder. See RAMBAN and RITVA to 69a. The SHULCHAN ARUCH (YD 234:5) cites both opinions.)
According to the Rambam, perhaps it is this Halachah which the Mishnah intends to teach, according to the Gemara's conclusion. The Mishnah teaches that when the father heard the Neder before the divorce, even if he did Hafarah before the Arus divorced her the second Arus cannot annul his portion on the next day, because the second Arus must do Hafarah on the same day on which the father does Hafarah. (This may also be the intention of the SEMAG cited by the LECHEM MISHNEH, who brings support for the Rambam's ruling from this Gemara. Although the Lechem Mishneh challenges the Semag's proof, according to the above explanation the Semag's proof is justified.)

72b----------------------------------------72b

3) APPOINTING A "SHALI'ACH" TO DO NOTHING
QUESTION: The Gemara attempts to prove that the husband may do Hafarah before he hears his wife's Neder from the Halachah which permits the husband to appoint a Shali'ach to annul his wife's Nedarim even before he hears them. The RAN asks that this Halachah does not seem to prove anything. If the husband appoints a Shali'ach, perhaps the Shali'ach may annul the Neder only when he hears it, and there is no proof that one may annul his wife's Neder before he hears it.
The Ran answers in the name of TOSFOS that the husband cannot appoint the Shali'ach to do Hafarah at a future date when the husband still has not heard the Neder, since he (the husband) did not yet hear the Neder at that point and thus he cannot do Hafarah himself. Whenever he cannot do Hafarah, he also cannot appoint a Shali'ach to do Hafarah.
How does this answer address the question? This answer explains only why the husband cannot appoint the Shali'ach to do Hafarah when the husband did not appoint the Shali'ach to hear the Neder on his behalf as well. Perhaps if he appoints the Shali'ach to hear the Neder for him, the Shali'ach may hear the Neder and annul it for him!
ANSWER: The ROSH writes that the Shemi'ah, hearing, of a Shali'ach cannot constitute a Shemi'ah for the husband, because a person cannot appoint someone else to be his emissary for something passive (such as hearing). Shelichus must constitute an act. Since hearing is not an act, one cannot appoint a Shali'ach to do it on his behalf.
The KETZOS HA'CHOSHEN (CM 182) compares this to what the TOSFOS RID writes in Kidushin (41a). The Tosfos Rid writes that the reason why one cannot make a Shali'ach to don Tefilin for him or to hold the Lulav for him is that these acts must be done with one's body. When the Shali'ach does the Mitzvah with his own body, his Mitzvah cannot be attributed to the one who appointed him. Why, though, may one not appoint a Shali'ach to act in the capacity of his own body? The answer is that the Tosfos Rid maintains, like the Rosh, that one cannot appoint a Shali'ach to be passive.

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