100b----------------------------------------100b

1) A KOHEN IN DOUBT ABOUT THE IDENTITY OF HIS FATHER
QUESTION: Shmuel maintains that a Gezeirah d'Rabanan prohibits a Kohen who does not know the identity of his father from serving in the Beis ha'Mikdash, even though he knows that the man who fathered him was a Kohen. Although he is a valid Kohen and the laws of Kehunah apply to him, he may not perform the Avodah in the Beis ha'Mikdash.
The Gemara explains that the Gezeirah d'Rabanan applies only when the Kohen's doubt is due to the fact that his mother was involved in promiscuous relations. The Gezeirah does not apply when the doubt about his father's identity arose for reasons unrelated to promiscuity. For example, his mother was married to one Kohen who died, and within three months she married another Kohen. Seven months later she gave birth to a son. The son is a "Safek Ben Tish'ah la'Rishon, Safek Ben Shiv'ah la'Sheni" -- there is a doubt whether his father was the first Kohen or the second Kohen. In such a case, he is permitted to perform the Avodah.
The Gemara attempts to disprove Shmuel's assertion that the Rabanan prohibited a Kohen from serving in the Beis ha'Mikdash when he is in doubt about the identity of his father even when that doubt arose as a result of his mother's promiscuity. The Gemara cites the Mishnah (100a) which states that a Kohen who is a "Safek Ben Tish'ah la'Rishon, Safek Ben Shiv'ah la'Sheni" may not become Tamei for either of his two possible fathers upon their deaths. The Gemara asks, why does the Mishnah need to prohibit him from becoming Tamei for the first possible father? In the case of a woman who married a second Kohen after the death of her first husband who was a Kohen, there is no need to teach that the son may not become Tamei for his mother's first husband (who might be his father) -- he was not yet born at the time his father died! If the Mishnah refers to a case in which the woman married a second Kohen after her first husband divorced her, the son should be allowed to become Tamei for the first man regardless of who his actual father is: if he is the son of the first man, he may become Tamei for him because he is his real father, for whom a Kohen is allowed to become Tamei. If he is the son of the second man, he has the status of a Chalal (born from a prohibited union between a Kohen and a divorcee), and a Chalal is permitted to become Tamei!
The Gemara asserts, therefore, that the doubt about the identity of the Kohen's father must be due to his mother's promiscuity. The first Kohen was not married to her at all and thus he did not have to divorce her, and he is still alive when she marries the second Kohen. The son does not know who his true father is. Accordingly, the Mishnah teaches that even though the son does not know who his father is because of his mother's promiscuity, he still may serve in the Beis ha'Mikdash.
RASHI (DH Ela Lav b'Znus) writes that when the Gemara says that she was involved in illicit relations, it means that she was promiscuous with both the first Kohen and the second Kohen.
Why does Rashi write that both men lived illicitly with the woman? It suffices to say that she was promiscuous with only the first Kohen, and that she married the second Kohen! As long as she was not married to the first Kohen she is not a divorcee, and her child, if his father is the second Kohen, is not a Chalal. (MAHARSHA)
In fact, the Mishnah clearly states that after she lived with the first Kohen, "she married [another Kohen] and gave birth." According to Rashi's explanation, the term "she married" in the Mishnah is imprecise and really means that she had illicit relations with him. Why does Rashi alter the straightforward meaning of the Mishnah?
ANSWERS:
(a) The MAHARSHA explains that Rashi's words are imprecise. Rashi means that the significant point is that the woman's relationship with the first Kohen was one of promiscuity and not marriage. Whether her relationship with the second Kohen was one of promiscuity or one of marriage is not relevant.
This answer is difficult to accept. Why does Rashi write that she had illicit relations with both men if it is not necessary to explain the Gemara that way? (YASHRESH YAKOV)
(b) The BEIS SHMUEL (EH 3:16) suggests that Rashi understands that when the Gemara says that the Gezeirah d'Rabanan (according to Shmuel) applies only in a case in which the son is in doubt about his father's identity because of his mother's promiscuity, it means that the mother was promiscuous with both Kohanim (with all of the possible men who might be his father). If she was promiscuous with only one Kohen, the Gezeirah does not disqualify the son from performing the Avodah, because one of the possible fathers was indeed married to her.
However, the Beis Shmuel himself questions this approach. If the Gezeirah disqualifies the son from Avodah only when his mother had illicit relations with all possible fathers, why does the Gemara not give a simple answer for its question on Shmuel: the second Kohen was married to her and did not have illicit relations with her? In that case, since one of the possible fathers was married to her the Gezeirah should not apply! It must be that the Gezeirah applies even when only one of the possible fathers had illicit relations with her.
(c) The CHELKAS MECHOKEK (EH 3:12) explains that Rashi's intention is to address a different question. If the first Kohen had illicit relations with her and the second Kohen married her, then the rule of "Rov Be'ilos Achar ha'Ba'al" (see 69b) should apply. That rule states that the child was most likely fathered by the man to whom she was married, and not by the man with whom she had illicit relations.
This rule normally applies to a case in which a woman committed adultery while married and was then found to be pregnant. The rule of "Rov Be'ilos Achar ha'Ba'al" states that the child is assumed to be her husband's child and was not conceived through an adulterous act.
However, the Acharonim (Beis Shmuel and others) point out that this rule applies only when the woman had illicit relations while she was married. In this case, however, she was promiscuous with the first Kohen before she was married to the second Kohen, and thus it is not more likely that the child was fathered by the second Kohen (to whom she is now married) than by the first Kohen (with whom she was promiscuous). (Moreover, the only possibility that the child's father is the woman's husband (the second Kohen) is that he was conceived on the very first day of the marriage, since he was born after seven months of pregnancy. This is an unlikely possibility which certainly counteracts the application of the rule "Rov Be'ilos Achar ha'Ba'al.")
(d) The YASHRESH YAKOV and ARUCH LA'NER explain that Rashi's intention is to address a different question. When a woman has illicit relations, she is careful to be "Mis'hapeches" (to turn herself over) to avoid pregnancy (35a; see also Rashi to 69b, DH Aval b'Znus). Since it is assumed that she was "Mis'hapeches" after her act of Z'nus with the first Kohen, and since she married the second Kohen, there are grounds to assume that the second Kohen is the true father of the child.
Why, then, is there any doubt? It must be that she was promiscuous with both men. The fact that she became pregnant shows that she was not "Mis'hapeches," and thus there is an equal possibility that either Kohen is his father.
(Rashi may have derived this point from the fact that the Gemara does not give the answer which the Beis Shmuel suggests, that perhaps Shmuel's Gezeirah applies only when the mother had illicit relations with both potential fathers, while the Mishnah refers to a case in which the mother had illicit relations with only the first potential father. The fact that the Gemara does not offer this answer indicates that when only one of the potential fathers had illicit relations and not the other, the child's paternity indeed is attributed to the second father, and there is no doubt about his lineage. Therefore, this must not be the case which the Mishnah discusses.)
(e) RAV YAAKOV D. HOMNICK proposes an original explanation for the words of Rashi.
He first questions the Gemara's distinction between the case of a doubt that arose due to the mother's promiscuity and a doubt that arose due to the mother's remarrying within three months of her first marriage. Why does the Gemara assert that the Gezeirah d'Rabanan that prohibits the Kohen from serving in the Beis ha'Mikdash applies only when the doubt about the identity of his father arose due to the mother's promiscuity, but not when the doubt arose due to the mother's marriage to a second Kohen within three months of her first marriage? In both cases, the Kohen's patrilineal lineage is in question, and the Gemara derives from a verse that a Kohen must have clarity and certainty about his patrilineal lineage -- "Zar'o Meyuchas Acharav." Whether the mother remarried too early or whether she was promiscuous, the Kohen has a doubt about who his father is and thus the requirement for "Zar'o Meyuchas Acharav" is not fulfilled!
The answer is that it is true that the Rabanan enacted that the Kohen may not serve in the Beis ha'Mikdash unless he has definite knowledge about his patrilineally descent. However, their enactment was made not on the Kohen who was born (and who has a doubt about the identity of his father), but on the Kohen who bore him. That is, the Rabanan imposed a penalty on the Kohen who did an act that created a doubt about the lineage of his offspring, and they gave his offspring the status of a Chalal d'Rabanan. Accordingly, they imposed the penalty only on a Kohen who did an improper act -- an act of promiscuity, but not on a Kohen who did nothing wrong. Hence, if the second Kohen was married to the woman, the Gezeirah d'Rabanan does not apply to him (i.e. to disqualify his offspring) since he did nothing wrong. (Even though he married her before three months had passed from the time of her first marriage, he is not penalized since the very act of marriage was an act of a Mitzvah.)
Moreover, the first Kohen with whom the woman lived out of wedlock did nothing to create a doubt about the lineage of his offspring. Even if their illicit union led to the birth of a son, that son is a Kohen who knows exactly who his father is. Rather, the Rabanan's penalty is due solely to the improper conduct of the second Kohen who lived with the woman illicitly (before three months had passed from the time she lived with the first Kohen).
Therefore, there is no basis for the suggestion that the Gezeirah d'Rabanan should apply in a case in which the woman lived illicitly with the first Kohen but married the second. It applies specifically in a case in which the woman was promiscuous with both Kohanim, as Rashi writes.

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