1) THE RABANAN'S AUTHORITY TO UPROOT A MARRIAGE
QUESTIONS: The Gemara states that in certain situations, the Rabanan -- in order to end a marriage -- uproot the Kidushin retroactively so that the marriage will no longer exist. The Gemara here discusses a situation in which a man gives a Get to his wife on condition that he does not return from abroad, and then circumstances beyond his control prevent his return. Although mid'Oraisa the Get is not valid (since a fulfillment of a condition against one's will is not considered a fulfillment of the condition), the Rabanan instituted that the Get takes effect (for the reasons the Gemara describes). What authority do the Rabanan have to make the Get valid when, mid'Oraisa, it is not valid? The Gemara explains that the Rabanan utilized their authority to uproot the Kidushin (retroactively) -- "Afke'inhu Rabanan l'Kidushei Minei."
Another example of a situation in which the Rabanan remove the Kidushin is when a man sends a Get to his wife and then annuls the Get after the Shali'ach has departed, without informing the Shali'ach of the annulment. Although the Get is not valid when the Shali'ach gives it to the woman, the Rabanan proclaimed that it takes effect by using their authority to uproot the Kidushin.
How does this mechanism of uprooting the Kidushin work? When the Rabanan uproot the Kidushin, is it considered as though the man and woman were never married? If it indeed works this way, then it should be possible to remove the status of a Mamzer from a child born to a married woman through rape or an adulterous relationship. By uprooted the Kidushin retroactively (such as by having her husband send her a Get with a Shali'ach and then annul the Get), the child's status as a Mamzer should be able to be removed. Similarly, in the same manner a man should be able to save his wife from being punished with Misah when she willfully committed adultery.
In addition, the PNEI YEHOSHUA points out that if the Rabanan uproot the Kidushin retroactively, then if the brother of the husband later marries the woman (who is forbidden to him as "Eshes Achiv"), the Kidushin should take effect mid'Oraisa (and she should require a Get if she wants to leave him) since she is not his "Eshes Achiv." Is this indeed the Halachah?
Another question is that if the Rabanan are able to remove Kidushin in such a manner, then why do they not use it in a broader context -- such as to permit Agunos to remarry? For example, in a case in which a husband drowns at sea ("Mayim she'Ein Lahem Sof") and there is no positive testimony that he is dead, the Halachah is that his wife may never remarry. The Rabanan should permit her to remarry by exercising their authority to uproot the Kidushin retroactively!
ANSWERS:
(a) TOSFOS in Gitin (33a) writes that it is true that where the Rabanan uproot the Kidushin, a child who is a Mamzer due to the presence of the Kidushin becomes legitimate, and the woman becomes exempt from punishment for committing adultery (and, presumably, if she marries the brother of her husband, the Kidushin with him will take effect). However, a person cannot intentionally take advantage of this power of the Rabanan to correct the status of a Mamzer. In such a case -- where a man intentionally sends a Get to his wife with a Shali'ach and then annuls the Get in order to save his wife from punishment or to make his wife's illegitimate children legitimate -- the Rabanan do not uproot the Kidushin. They uproot the Kidushin only when a man annuls the Get innocently, with no ulterior motives.
Why do the Rabanan not exercise their authority to uproot Kidushin in order to permit Agunos to remarry? The RAMBAN and RASHBA explain that the Rabanan exercise this power only where there is some form of Get that was already given. Although the Get itself is not valid, the Rabanan uproot the Kidushin based on the giving of that Get.
This also seems to be the intention of RASHI here who repeatedly writes that the Rabanan uproot the Kidushin "when a Get is given." (Rashi in Shabbos (155b) writes that the reason the Rabanan permitted a woman to remarry based on the testimony of a single witness is because of the principle of "Afke'inhu." Here, Rashi explains why the Rabanan do not apply "Afke'inhu" to permit Agunos in other situations. Rashi is explaining that in the case of a single witness who testifies that the husband died, there is at least some sort of testimony that he died, and thus there is a basis for the Rabanan to uproot the Kidushin. According to Rashi, wherever there is some form of Get or some form of testimony of death, the Rabanan may apply "Afke'inhu.")
(b) The RAMBAN and RE'AH write that although the Rabanan uprooted the Kidushin d'Oraisa, they nevertheless established in its place a Kidushin d'Rabanan. Therefore, the child born to the woman from another man will still be a Mamzer d'Rabanan, and the relatives of the husband will be prohibited to the woman mid'Rabanan. Similarly, she will be prohibited mid'Rabanan to marry a Kohen.
(c) The Rishonim here (RAMBAN, RASHBA) and in Gitin quote the RASHBAM (see also PNEI YEHOSHUA here) who suggests that when a condition of the Get is fulfilled against the husband's will, and when a husband annuls a Get after having sent it with a Shali'ach, the Kidushin is not uprooted retroactively, but rather it is uprooted from now on -- "mi'Kan ul'Haba." (See also SHITAH MEKUBETZES who quotes the words of the Rashbam as found in a marginal note in a manuscript of Rashi's commentary.)
The Rashbam explains that the Gemara means that the Rabanan have the right to uproot the Kidushin retroactively, and if they do so, all of the Be'ilos retroactively become Be'ilos of Z'nus. Since nobody wants his Be'ilos to become Be'ilos Z'nus, when he gives a Get with a condition he has in mind that even if the condition is fulfilled later against his will he still wants the Get to be valid. Similarly, when a man annuls a Get, since he knows that the Rabanan will make his Be'ilos into Be'ilos Z'nus if the Get is annulled, he does not really want to annul the Get.
The Ramban asks that according to this understanding, in a case in which a woman is only betrothed (with Erusin) and her husband gives her a Get on condition or annuls a Get that he sent with a Shali'ach, the Kidushin should be uprooted retroactively since the man has not had relations with his wife and thus has no fear that his Be'ilos will be made into Be'ilos Z'nus. The Ramban answers that even though there was no Be'ilah, the husband has in mind that the Get should take effect even if the condition is fulfilled against his will, because he knows that his intention will not prevent the Get from taking effect (since the Kidushin will still be uprooted against his will). Therefore, he intends for the Get to take effect under any circumstance.
(d) RASHI cites a fourth explanation in the name of "all of my teachers." This explanation is found in PERUSH RABEINU GERSHOM to Bava Basra (48b). He explains that all Kidushin nowadays is only mid'Rabanan in any case, and that is why the Rabanan are able to uproot it from now on. Rabeinu Gershom asserts that Kidushei Kesef (and Kidushei Shtar) are mid'Rabanan, while Kidushei Bi'ah -- which is mid'Oraisa -- cannot make a Kidushin d'Oraisa nowadays since the Rabanan prohibited one from being Mekadesh a woman with Bi'ah (Kidushin 12b). The Rabanan went further and said that since everyone is "Mekadesh Al Da'as d'Rabanan," all Kidushei Bi'ah does not work mid'Oraisa nowadays (and it makes only a Kidushin d'Rabanan).
(Once the Rabanan instituted that one can be Mekadesh a woman with Kidushei Kesef, it became an act of effrontery to be Mekadesh a woman with Bi'ah. Therefore, when the Rabanan instituted Kidushei Kesef, they also instituted that a person may not be Mekadesh with Bi'ah and they annulled that form of Kidushin, based on the premise that when a person gets married he does so according to the will of the Rabanan.)
Rashi and the other Rishonim challenge the explanation of Rabeinu Gershom.
1. Rabeinu Gershom's assertion that Kidushei Kesef and Kidushei Shtar are mid'Rabanan contradicts the Gemara (Kidushin 2a) which clearly derives Kidushei Kesef from a Gezeirah Shavah in the Torah.
Apparently, Rabeinu Gershom understand that the Gezeirah Shavah is not an actual Gezeirah Shavah mid'Oraisa, but is only an Asmachta. (The same applies to Kidushei Shtar, which is derived through a comparison with a Get (Kidushin 9b). Rabeinu Gershom understands that comparison as only an Asmachta.)
2. Rashi asks that a Ne'arah Me'urasah is defined as a woman who was assumed to be a Besulah at the time of the Nisu'in but was found to have had relations with another man while she was an Arusah. The Torah punishes such a woman with Sekilah. How can the Torah consider her to be a Besulah at the time of Nisu'in if, mid'Oraisa, there is no such thing as Kidushei Kesef or Kidushei Shtar? The only way she could have become an Arusah mid'Oraisa is through Kidushei Bi'ah, in which case she would not be a Besulah and thus it is not possible for there to be a case of Ne'arah Me'urasah!
Rabeinu Gershom apparently is not bothered by this question because he understands that the Kidushin mid'Oraisa could be done with a Bi'ah she'Lo k'Darkah. Such a Bi'ah serves to make the woman an Arusah, but it does not make her a Be'ulah and she remains a Besulah. (See at length the Gemara in Kidushin 9b. Although the Gemara there rejects this possibility, perhaps Rabeinu Gershom understands that the Sugyos are arguing.)
3. Rashi asks that according to Rabeinu Gershom, a woman who gets married with Kidushei Bi'ah should be permitted to leave her husband without a Get. Rabeinu Gershom apparently understands that although the Rabanan removed the Kidushin d'Oraisa, they nevertheless substituted in its place a Kidushin d'Rabanan which requires a Get.

3b----------------------------------------3b

2) HALACHAH: THE "BI'AH" OF A NOCHRI
OPINIONS: The Gemara teaches that during an era when the wicked regime instituted that every Jewish Besulah was to be defiled by the local governor before her wedding, people started getting married on Tuesday to avoid the decree (since the officials knew that the Chachamim had instituted that a Besulah get married only on Wednesday). The Gemara says that those who were defiled by the governor were nevertheless permitted to live with their husbands afterwards (because the act was one of Ones), except for the wives of Kohanim, who become forbidden to their husbands even when raped.
It is clear from the Gemara that a woman who lives with a Nochri willfully is not be permitted to her husband. What is the Halachah if a married, Jewish woman commits adultery with a Nochri? Does she become prohibited to her husband and to the adulterer (if, for example, he later converts and becomes Jewish)? The Rishonim discuss this question at length.
(a) RABEINU TAM (cited by TOSFOS DH v'Lidrosh) writes that the Bi'ah of a Nochri is like that of a Behemah. Therefore, a married woman is not Chayav Misah if she willfully commits adultery with a Nochri. This is also the opinion of the BA'AL HA'ME'OR and the RAMBAN (in Milchamos) in Sanhedrin (74b). However, the reason they give for exempting her from Misah is that the Torah says that only a man who commits adultery with "Eshes Re'ehu" ("the wife of one's fellow man") is Chayav Misah, and when a Nochri commits adultery with a Jewish man's wife, she is not called "Eshes Re'ehu."
Rabeinu Tam adds that for the same reason, if the Nochri later converts, he is permitted to marry the woman with whom he lived, even though normally a woman who commits adultery is prohibited both to her husband and to the adulterer. In this case, the Nochri may marry her after he converts, because his Bi'ah with her was like the Bi'ah of a Behemah which is not the type of Bi'ah that makes a woman forbidden to her adulterer.
The RIVAM (cited by Tosfos, ibid.) understands that Rabeinu Tam means that not only is the Nochri permitted to marry the woman (after he converts), but even the husband is permitted to his wife after she committed adultery with a Nochri. However, he strongly opposes this ruling based on the Gemara here which implies that a woman who willfully lives with a Nochri becomes forbidden to her husband.
(Moreover, if Rabeinu Tam means that adultery with a Nochri does not prohibit the woman to her husband or to the adulterer, he should also rule that when the woman's husband is a Kohen she remains permitted to him. However, the Gemara clearly says that she is prohibited to her husband if he is a Kohen! The answer to this question may be that that the prohibition to a Kohen is not because of Tum'ah, that she became defiled (which is the reason for her prohibition to her husband and to the adulterer), but it is because of the Isur of "Zonah." The Gemara here maintains that even Bi'ah b'Ones renders a woman a Zonah (see Yevamos 56b and 59b).)
Perhaps Rabeinu Tam had a different intention. Rabeinu Tam means only that the woman is permitted to the adulterer, but not to her husband or to a Kohen, as the SHITAH MEKUBETZES (DH v'Ivra) writes. The logic behind this distinction is that since the Nochri's Bi'ah is not the same as that of a Jew because of the element of "Zirmas Susim Zirmasam," the woman is not Chayav Misah for such a Bi'ah. For the same reason, the adulterer is not prohibited to the woman, as his Bi'ah was not the type of Bi'ah which the Torah punishes with Misah, and we do not find that such a Bi'ah forbids her to the adulterer.
She is forbidden to her husband, however, because she was unfaithful to him, and the Torah says that if a woman is unfaithful to her husband she becomes forbidden to him; it makes no difference whether she was unfaithful to him with a Nochri or with a Jew. In summary, the prohibition to her husband depends on her being unfaithful, while the prohibition to the adulterer depends on the Bi'ah being considered a normal Bi'ah. (See MISHNEH L'MELECH, Hilchos Yibum 6:19, who discusses the extent to which we compare the woman's status to her husband with her status to the adulterer.)
This indeed is the opinion of RABEINU YECHIEL (cited by the RITVA here and by the MORDECHAI in Sanhedrin #720). Rabeinu Yechiel rules that if a Nochri lives with a married, Jewish woman, he is permitted to marry her after he converts, since he was permitted to her at the time he had relations with her (since he was a Nochri), and when he converts he becomes like a "Katan she'Nolad" (see also RASHASH here). This implies that if he had been forbidden to her while he was a Nochri, the prohibition would not have been revoked because of "Ger she'Nisgayer k'Katan she'Nolad Dami."
Accordingly, Rabeinu Tam is giving the reason why the prohibition does not apply to the Nochri while he is a Nochri, and Rabeinu Yechiel is adding why the prohibition does not apply to him when he converts. Indeed, the CHASAM SOFER and TOSFOS YOM HA'KIPURIM (Yoma 82b) explain that Rabeinu Tam means to say the same as Rabeinu Yechiel.
(b) The ROSH (1:4, and in TOSFOS HA'ROSH) also rules that when a woman commits adultery with a Nochri and then he converts, she is permitted to marry him, as Rabeinu Tam says, but for a different reason. The Rosh asserts that a woman is prohibited from marrying her adulterer only when she was permitted to him before the Z'nus. Since she is prohibited to marry a Nochri even before the Z'nus, the Torah does not prohibit her to him when he converts after she committed adultery with him.
The TERUMAS HA'DESHEN (#29) discusses the Rosh's view in a case in which a woman commits adultery with the husband of her sister, and then her sister dies. Following the logic of the Rosh, she should be permitted to the adulterer, because at the time of the Z'nus she was prohibited to him (because of "Achos Ishto").
The Terumas ha'Deshen concludes that even the Rosh permits her only in the case of a Nochri who converts, because a Nochri is always forbidden to the woman. If he converts, he is not the same person anymore because he is like a "Katan she'Nolad." Therefore, the prohibition to the adulterer will not apply when the Nochri converts. In contrast, the husband of her sister is prohibited to her only as long as her sister is alive. Therefore, when she commits adultery with him, the prohibition to marry her adulterer will apply.
(c) The RIVAM rejects Rabeinu Tam's argument entirely. He rules that the woman is prohibited to the Nochri with whom she committed adultery.
HALACHAH: The SHULCHAN ARUCH (EH 178:19) rules like Rabeinu Yechiel and the Terumas ha'Deshen, that the woman is permitted to the Nochri when he converts, but she is not permitted to the husband of her sister after her sister dies.
3) UPROOTING A "TAKANAH D'RABANAN" IN THE FACE OF DANGER
QUESTION: The Gemara says that if a wicked regime were to institute that anyone who marries a Besulah on Wednesday is to be killed, the Rabanan would uproot the Takanah d'Rabanan and would not require a Besulah to get married on Wednesday.
However, the Gemara later says that if a wicked regime decrees that any Besulah who gets married on Wednesday must live with the governor first, then even though there is a concern that some women, the Tzenu'os, might give up their lives, the Rabanan do not uproot the Takanah of getting married on Wednesday, because "evil decrees are wont to be retracted, and we do not uproot a Takanah d'Rabanan because of an evil decree which will eventually be retracted."
According to the Gemara later, why are the Rabanan prepared to uproot their Takanah if the regime decrees that whoever gets married on Wednesday will be killed? That, too, is an evil decree that will eventually pass!
ANSWERS:
(a) TOSFOS (DH Takanah) explains that if the regime makes a decree to kill anyone who gets married on Wednesday, the Rabanan would not have to uproot their Takanah because they could institute a different day for getting married instead of Wednesday. Such a change would satisfy the governor, since he would be content with the knowledge that he was able to cause a change in the Halachah of the Jews. Since his intention in making such a decree was clearly to prevent the Jews from observing the Halachah, it will not bother him if he finds that everyone is getting married on another day.
However, when the governor institutes a decree that he will have relations with every Besulah who gets married on Wednesday, he obviously is interested in personal pleasure and not in abolishing the Jews' practice. (This also explains why there is no requirement "to be killed and not to transgress" in this case, even though the Halachah is that when Nochrim attempt to make the Jews change any religious practice with the express intent to abolish the Jewish faith, there is a requirement "to be killed and not to transgress.") If the Rabanan were to institute that Besulos should get married on Tuesday, the governor would just change his evil decree to take all the woman who get married on Tuesday. Therefore, the Rabanan would have to avoid instituting a new day for getting married and abolish the Takanah of getting married on a specific day. Since they do not abolish any Takanah because of an evil decree, the Takanah remains in force.
This appears to be the intention of Rashi as well (DH v'Ne'akrei).
(b) The SHITAH MEKUBETZES explains that if the evil decree would have been to kill people who get married on Wednesday, the Rabanan certainly would have annulled their enactment in order to save lives. However, since the decree was only that the Besulos must be defiled by the governor, and there was no definite danger to lives but only a possible danger that a modest woman might give up her life in order to avoid living with the governor, the Rabanan did not annul their enactment, as there is a possibility that no lives will be lost by the time that the evil decree is revoked. (See also PNEI YEHOSHUA.)
(c) The RITVA answers that in the case of the decree that each Besulah must be defiled by the governor, the Rabanan did not uproot their enactment to get married on Wednesday because the only concern is that some women will give up their lives "Lifnim mi'Shuras ha'Din," beyond the letter of the law. For such a concern, the Rabanan do not abolish an enactment. If, however, there would be a concern that a person would have to give up his life according to the letter of the law, then the Rabanan certainly would abolish their enactment.
As the SHITAH MEKUBETZES here points out, the Ritva apparently follows his opinion as expressed elsewhere (19a), where he writes that for any Mitzvah for which a person is not required to give up his life, he is prohibited to give up his life. (This is also the ruling of the RAMBAM in Hilchos Yesodei ha'Torah 5:4.) Accordingly, the Rabanan did not find it necessary to abolish their Takanah because of women who are acting improperly by giving up their lives when they are not supposed to do so (and they are prohibited to do so). This is the "Lifnim mi'Shuras ha'Din" to which the Ritva refers -- an act in error, not a laudable one.

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