1) A "SAFEK" THAT INVOLVES MORE THAN ONE PERSON
OPINIONS: The Mishnah states that if a city was under siege and conquered by Nochrim, all of the wives of Kohanim in the city are prohibited to their husbands. In the Gemara, Rav Idi bar Avin states that if there is a place in the city where the women could hide, they are permitted to return to their husbands. Rebbi Yirmeyah inquires what the Halachah is in a case in which the hiding place is large enough for only one woman. Do we rule that since some of the women have nowhere to hide and are prohibited to their husbands, all of them are prohibited out of doubt, or do we rule that even though only one woman can hide, each woman is permitted when she comes to Beis Din by herself to ask if she is permitted to her husband, since we may assume that it was she who hid in the hiding place?
The source of such a leniency is the case of "two people and two paths," where one path is Tamei (there is an item of Tum'ah in it) and one path is Tahor, and one person walked on each path. If each person asks Beis Din about his status (whether he is Tamei or Tahor) independently of the other, they are both Tahor. If, however, they come together and ask, they are both Tamei. If one of them asks for both of them, there is a Machlokes between Rebbi Yosi and Rebbi Yehudah whether they are Tahor or Tamei (Rebbi Yehudah says that they are both Tahor, and Rebbi Yosi says that they are both Tamei).
The logic behind this Halachah is the principle, "Safek Tum'ah b'Reshus ha'Rabim Tahor" -- when there is a doubt about Tum'ah in Reshus ha'Rabim, the subject in question is Tahor. (This is a Halachah l'Moshe mi'Sinai and is not based on a logical reason for resolving the Safek, but is a tool which instructs Beis Din how to approach the Safek: as long as the case which Beis Din is addressing involves a question of Tum'ah in Reshus ha'Rabim, they are to rule that it is Tahor.) Since each person has a different, independent question (that is, his walk through one of the paths), Beis Din rules that each one is Tahor. Only when they both come to Beis Din and present their cases together does Beis Din treat the question as one general case involving both persons, in which it is impossible to say that both are Tahor since one of the two is definitely Tamei.
TOSFOS in Pesachim (10a) writes that when the Gemara rules that both persons are deemed Tamei when they come together to ask about their status, it means that they are Tamei only mid'Rabanan. Tosfos explains that the logic behind this is that even if they both come together, mid'Oraisa the two questions are viewed as two independent cases, since each Safek involves only one of the two people (was this path Tamei, or was the other path Tamei). Tosfos in Nidah (60a) adds that the reason why the Rabanan were stringent to make them both Tamei is that it would look very odd for Beis Din to issue a self-contradictory ruling (that both are Tahor). (When they come separately, however, this is not a concern, because there is no single verdict which involves both of them but rather two completely separate verdicts.)
According to the logic of Tosfos, it is difficult to understand why Rebbi Yehudah rules that if one person asks on behalf of both, they are both deemed Tahor -- in this case, too, the Beis Din is issuing a self-contradictory ruling that they are both Tahor! Tosfos here (DH b'Ba) answers this question by saying that Rebbi Yehudah refers only to where one person asked about himself, and only after he received his ruling did he ask about his friend. Since both questions were posed separately, there is reason to say that Beis Din may make both of them Tahor and it does not appear to be a single, self-contradictory ruling.
(a) Tosfos understands that the Gemara concludes that the case of the women in a besieged city where there is a hiding place for only one is comparable to two women who come to Beis Din together to ask whether they are permitted to their husbands. Accordingly, all of the women should be prohibited, but since there is no certainty that any of them was raped Beis Din may rule that they are permitted. Tosfos learns that the case is equivalent to two women who ask at the same time, and therefore even according to Rebbi Yehudah the women should be prohibited.
(b) Rashi disagrees with Tosfos. Rashi understands that our case is comparable to the case of one person who asks on behalf of both, in which case they would all be prohibited only according to Rebbi Yosi.
It is possible to explain the Machlokes between Rashi and Tosfos about how to understand the Gemara in the following manner. Tosfos learns that as long as Beis Din is presented with a case that involves both parties, they may not issue a ruling that permits either one of them since it might be inferred from that ruling that the other one is also permitted, and that would be a self-contradictory ruling (as it is impossible for both of them to be permitted). Therefore, there is no difference between whether both people involved in the question come together and present their Safek, or whether one person presents the question on behalf of both of them. Therefore, Tosfos explains that Rebbi Yehudah is lenient only because the person did not present both persons' Sfeikos at the same time. Tosfos also explains that the case of the besieged city is comparable to when both persons come to Beis Din together.
Rashi (Pesachim 10a), on the other hand, explains that Rebbi Yehudah is lenient even in a case in which one person presented both of their Sfeikos together. Rashi explains that Rebbi Yehudah agrees that when both come to Beis Din together, Beis Din cannot issue a ruling that both are Tahor (or permitted to their husbands, in the case of the Gemara here). When the second person does not come personally to Beis Din to present his question, and his question is brought up merely as part of the first person's question, Beis Din does not have to issue a ruling that involves both of them. Beis Din simply says that the first person is Tahor, and we may infer that the second one is also Tahor. According to this approach, it is clear that in the case of the besieged city, when not all of the women come to Beis Din together, only Rebbi Yosi rules that all of the women are prohibited to their husbands.
The Gemara in Pesachim (10a) discusses a case in which a rodent brought Chametz into one of two houses just before Pesach, and it is not known which of the house now needs another Bedikas Chametz. The Gemara there says that this case is the same as the case of "two paths." The TUR derives from this comparison that if the owners of both houses come to the Rav together and ask if they are required to search their houses for the Chametz, the Rav must rule that both must perform another Bedikah. If they come to the Rav separately, the Rav rules that neither one needs to perform another Bedikah. The RAMBAM does not differentiate between when they come together and when they come separately, a view which the Tur questions from the Gemara in Pesachim which equates this case with the case of "two paths." The MISHNEH L'MELECH answers that the Rambam's opinion is based on the Gemara here in Kesuvos, which teaches that since it is not certain that any of the women were actually raped, they are all permitted to their husbands even though they come together to Beis Din. Likewise, in the case of the Chametz, it is possible that the rodent ate the Chametz and thus neither house has any Chametz in it.
According to Tosfos here, who explains that whenever Beis Din is asked a Safek that involves both persons, both Rebbi Yosi and Rebbi Yehudah agree that Beis Din must rule stringently for both persons, in the case of the Chametz the Halachah should be that even if only one of the homeowners comes to ask the question he is required to perform another Bedikah. This is in contrast to the Tur who differentiates between where they come to ask together and where they come separately. It seems that the Tur follows the approach of Rashi.

27b----------------------------------------27b

2) TRUSTING A WOMAN'S OWN MAIDSERVANT TO TESTIFY ABOUT HER
QUESTION: The Mishnah (27a) states that if a woman was captured, even a slave or maidservant is believed to testify that she was not defiled and she is permitted to marry a Kohen. The Gemara here infers from the Mishnah that even her own maidservant is believed to testify to her benefit. The Gemara challenges this from a Mishnah (Gitin 73a) that states that a divorced woman "may not seclude herself (Yichud) with her former husband unless there are witnesses present, even a slave or a maidservant, except for her own maidservant." The Mishnah there clearly states that her own maidservant is not believed to testify about her.
What is the Gemara's question from the Mishnah in Gitin? The reason her own maidservant is not trusted is because a woman is not embarrassed to sin in front of her own maidservant. It is not because her maidservant has no trustworthiness. Why, then, does the Gemara assume that since Yichud in her maidservant's presence is prohibited, her maidservant is not believed to testify that the woman was not defiled by her captors? One case is unrelated to the other! (RASHBA)
ANSWERS:
(a) The RASHBA answers that if there is a chance that the maidservant would reveal to others what her owner did, there would be no Isur of Yichud when she is present since her owner would be afraid that her maidservant will tell others what happened in private. Since the Mishnah in Gitin states that there is an Isur of Yichud in her presence, it must be that the maidservant would never reveal that her owner did anything wrong, even when questioned in court. For this reason, the Gemara assumes that the maidservant would not be believed to say that her owner was not defiled, since she would never admit it if something really happened.
Rav Ashi's answer in the Gemara is also in agreement with this premise. Although he says that the maidservant will not reveal what happened, this means that she will only be silent but not that she will lie and say that nothing happened when something did happen to her owner.
(b) Perhaps another approach may be suggested. The Gemara understands that if there is no Isur of Yichud in the presence of her maidservant, it must be that the maidservant is viewed not as a separate entity but as part of her owner, as the Gemara itself suggests in Rav Papa's answer, "her maidservant is like her." Accordingly, it makes sense that she may not testify for her owner, since the Mishnah (27a) says that "a person is not believed [to testify] about himself." (See Insight #4 below for a similar discussion with regard to a woman's husband.) When Rav Papa answers that the Mishnah agrees that her maidservant is not believed, he understands that the Mishnah agrees that her maidservant is a "part" of herself and thus she may not testify for "herself." (Indeed, the SHITAH MEKUBETZES cites the SHITAH YESHANAH who explains that this is the Gemara's intention when it says "her maidservant is like her.")
Further support for this approach is found in the RAMBAM. The Rambam (Hilchos Isurei Bi'ah 18:19) writes that a husband is not believed to testify for his wife since "one may not testify for himself, and so, too, her maidservant may not testify for her." The words of the Rambam imply that the reason the maidservant is not believed is because she is considered to be "part" of her owner.
3) WHY THE RABANAN WERE LENIENT WITH REGARD TO A "SHEVUYAH"
QUESTION: The Mishnah teaches in various places that the Rabanan were lenient with regard to a woman who was taken captive ("Shevuyah"). (For example, the Rabanan ruled that even a minor and a woman's servants are believed to testify that she was not defiled by her captors.) What is the reason for this leniency?
ANSWERS:
(a) TOSFOS (36b, DH v'Elu) writes that mid'Oraisa she does not have a "Chezkas Be'ulah" -- it is not assumed that she was defiled. The Isur of a Shevuyah to a Kohen is mid'Rabanan, and therefore the Rabanan were lenient when they applied their laws in the case of a Shevuyah. This is also the intention of Tosfos (27b, DH b'Mesichah, according to the Girsa of MAHARI LANDAU in the margin of the Gemara, and Tosfos to Kidushin 12b, DH Im) who writes that the Rabanan were lenient and permitted relying on the testimony of a person who is "Mesi'ach l'Fi Tumo" since the Isur of Shevuyah is mid'Rabanan.
(The NODA B'YEHUDAH (EH 1:66) explains that although a Shevuyah does not have a Chezkas Kashrus because Ovdei Kochavim are steeped in immorality (13b), the Rabanan were lenient with a Shevuyah because of the logic that a woman makes herself disgusting so that they will not be attracted to her ("Menavlah Nafshah"), as the Gemara says in Kidushin (13b). The Rambam, quoted below (b), also treats her situation as a Safek, without a Chezkas Kashrus. However, the MAHARSHA in Bava Kama (114b) writes that the Chezkas Kashrus alone allows Beis Din to be lenient in the case of Shevuyah.)
Tosfos (36b) questions this approach. If, mid'Oraisa, the Shevuyah is assumed to be a Besulah, why does a man who rapes her not have to pay a Kenas? Tosfos answers that mid'Rabanan she is treated like a Be'ulah in all respects, so that she will not think that she may marry a Kohen. Similarly, she does not receive the Kesuvah of a Besulah; the Rabanan enacted that she has the status of a Be'ulah with regard to all Halachos so that she will not come to marry a Kohen.
(The SHA'AR HA'MELECH (Hilchos Isurei Bi'ah 18:24) cites RASHI in Bava Kama (114b) who seems to disagree with Tosfos and maintains that the Safek of the status of a Shevuyah is a Safek d'Oraisa. However, Rashi's comments there refer to the Havah Amina of the Gemara. From his explanation of the Gemara's conclusion there it seems that the Gemara retracts this view and maintains that a Shevuyah indeed is only a Safek d'Rabanan. See Maharsha there.)
(b) The RAMBAM (Hilchos Isurei Bi'ah 18:17) writes that the reason why the Rabanan are lenient in the case of a Shevuyah is because the Isur created by a Safek is only mid'Rabanan. The Rambam apparently maintains that the Safek whether or not she was defiled is even a Safek d'Oraisa, but that the principle that a Safek d'Oraisa is deemed Asur is only mid'Rabanan. The Rambam follows his well-known view (Hilchos Avos ha'Tum'os 16:1, Hilchos Kil'ayim 10:27, Hilchos Tum'as Mes 9:12) that all Sfeikos d'Oraisa are Asur only mid'Rabanan.
According to the Rambam, it is clear why she is treated like a Safek Be'ulah even with regard to monetary matters, and she does not receive a Kenas if she is raped, and she does not receive the Kesuvah of a Be'ulah.
4) A PERSON MAY NOT TESTIFY ABOUT HIS WIFE
OPINIONS: The Mishnah says that Rebbi Zecharyah ben ha'Katzav testified that his wife was not defiled by Nochrim during their siege on Yerushalayim. The Chachamim did not accept his testimony, and they asserted that "a person may not testify about himself." In this case, Rebbi Zecharyah was not the subject of the testimony, so why was he not believed?
There are two basic approaches for understanding why a man in such a situation is not believed. The first approach is that the testimony of the woman or the testimony of her husband is not accepted simply because of the concern that each one might lie in order to prevent becoming prohibited to the other (that is, the husband is "Noge'a b'Davar"). According to this approach, the Mishnah says that the husband may not testify for his wife because he stands to benefit from the testimony and therefore he might be lying.
The second approach is that even in a case where the husband is not "Noge'a b'Davar," he still may not testify about his wife because of the rule that testimony must come from an external witness, an outside party, and not from the actual subject of the testimony (the "Ba'al Davar"). When the Mishnah says that a husband is not believed because one may not testify for himself, it may mean that he is not believed since the husband and wife are considered to be one unit ("Ishto k'Gufo"). Hence, the Mishnah means that his testimony about his wife is considered testimony for himself, since he and his wife are one (and the husband is the "Ba'al Davar").
This issue seems to be the subject of a dispute among the Rishonim.
(a) The RASHBA here and the MAGID MISHNEH (Hilchos Isurei Bi'ah 18:19) write that the husband and the wife are not believed even when they are "Mesi'ach l'Fi Tumo" (they randomly mention what happened in casual conversation, and not as testimony in court). They are not believed because they are suspected of attempting to trick Beis Din and are just pretending to be "Mesi'ach l'Fi Tumo" so that Beis Din will believe them. (The Rashba explains that although a person is believed when he says while "Mesi'ach l'Fi Tumo" that he is a Kohen (see 25b), Beis Din is particularly concerned that a Shevuyah might be lying since she was originally permitted to marry a Kohen and now she becomes prohibited to marry him.) They do not mention the additional possibility that the husband and his wife are considered to be a single entity.
(b) The SHITAH MEKUBETZES writes that the husband and wife are considered a single entity ("Ishto k'Gufo"), and therefore he is not believed to testify about her just as she is not believed to testify about herself.
The Mishnah states that Rebbi Zecharyah ben ha'Katzav was not believed to testify that his wife was not defiled. REBBI AKIVA EIGER in his commentary on the Mishnah points out that Rashi on the Mishnah does not mention that Rebbi Zecharyah was a Kohen. Only later in the Gemara does Rashi mention that Rebbi Zecharyah was a Kohen! Rebbi Akiva Eiger explains that from the Mishnah there is no proof that he was a Kohen because the Mishnah might simply be teaching that a husband is not believed to testify about his wife since she is considered part of him, "Ishto k'Gufo." Even though his testimony is not relevant to himself since she would be permitted to live with him even if she was defiled (if he is not a Kohen), he is not believed because he is the "Ba'al Davar," as he and his wife are one. (His testimony is relevant in case he dies and she wants to marry a Kohen.) Hence, there is no proof from the Mishnah that Rebbi Zecharyah was a Kohen since the Halachah of the Mishnah applies just the same even if the husband is not a Kohen. Only later, when the Gemara mentions that the Chachamim prohibited his wife from living with him, does Rashi need to explain that he was a Kohen!
According to the explanation of the Rashba who says that the husband's testimony is not accepted because of the concern that he is lying in order to permit his wife to live with him, perhaps a woman's husband who is not a Kohen would be believed since he has nothing to gain by lying (see HAGAHOS REBBI AKIVA EIGER to Even ha'Ezer 7:2). It seems that Rashi does not agree with the Rashba's explanation and maintains that the husband is not believed because of "Ishto k'Gufo."

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