1) TWO DIFFERENT MEANINGS FOR "EIN KORBAN TZIBUR CHALUK"
QUESTION: Rav states that when half of the Jewish people are Tahor and half are Tamei, we touch a Sheretz to a person who is Tahor and make him Tamei, and thereby create a majority of people who are Tamei. The entire Tzibur then brings the Korban Pesach on the fourteenth of Nisan in a state of Tum'ah.
The Gemara questions Rav's statement. Rav himself (79a) rules that when half of the people are Tamei and half are Tahor, those who are Tahor bring the Korban on Pesach Rishon (the fourteenth of Nisan) together as one group in a state of Taharah, and those who are Tamei bring the Korban on Pesach Rishon together as another group in a state of Tum'ah.
The Gemara attempts to resolve these two statements of Rav. It concludes that Rav's intention is as follows.
The Beraisa quoted immediately before the statement of Rav records three opinions about how to bring the Korban Pesach when half of the people are Tamei and half are Tahor. The Tana Kama says the two groups of people bring the Korban Pesach (on Pesach Rishon) separately, one group b'Taharah and one group b'Tum'ah. This is also the opinion of Rav (79a).
Rebbi Eliezer ben Masya says that when the number of Tamei people are greater than the number of Tahor people by only one, the Tamei group is not considered a majority, and each group brings the Korban Pesach separately. In order to make a majority, there must be at least two more people in the Tamei group than in the Tahor group.
Rebbi Yehudah maintains that even when half of the people (or even a single tribe) are Tamei and half are Tahor, everyone brings the Korban Pesach b'Tum'ah, because the people who are Tamei are considered a Tzibur, and once the Tzibur brings the Korban b'Tum'ah, everyone brings b'Tum'ah because of the rule of "Ein Korban Tzibur Chaluk."
The Gemara explains that Rav means that if there is a Tana who agrees with the Tana Kama of the Beraisa (who says that when half are Tamei and half are Tahor, the two groups bring the Korban separately) and also agrees with Rebbi Yehudah (that "Ein Korban Tzibur Chaluk"), then, according to that Tana, the people who are Tahor should not bring the Korban b'Taharah because they will embarrass those who must bring it b'Tum'ah (Rashi). Therefore, we cause one Tahor person to become Tamei so that a majority is now Tamei, and thus everyone may bring the Korban b'Tum'ah.
This Gemara is difficult to understand. How can the Gemara suggest that Rav means, "If there is a Tana who agrees with both the Tana Kama and with Rebbi Yehudah"? That Tana is Rebbi Yehudah! Rebbi Yehudah maintains that when half of the people are Tamei and half are Tahor, each group is considered a Tzibur by itself, and the two groups should bring the Korban Pesach separately. However, the principle of "Ein Korban Tzibur Chaluk" teaches that they must bring the Korban together. Why, then, does Rav say that the entire Tzibur brings the Korban together only when a majority is Tamei, which is accomplished by being Metamei one of the Tahor people? (DEVAR SHMUEL)
Furthermore, RASHI (end of DH Ela) says that the reasoning behind the principle of "Ein Korban Tzibur Chaluk" is that it is a disgrace for those who are Tamei when others, who are Tahor, bring the Korban b'Taharah. This reasoning implies that it is important not to bring the Korban b'Taharah in such a situation. However, when the Beraisa presents the opinion of Rebbi Yehudah who says "Ein Korban Tzibur Chaluk," Rashi (DH Ya'asu) says that those who are Tahor may bring the Korban b'Tum'ah "if they want," but they do not have to bring it b'Tum'ah. If the reasoning behind "Ein Korban Tzibur Chaluk" is that it would be a disgrace for those who are Tamei when others bring the Korban b'Taharah, then those who are Tahor should have no option but to bring it b'Tum'ah!
Finally, Rashi (79a, DH Tehorin), when he comments on the opinion of Rav Kahana, implies that "Ein Korban Tzibur Chaluk" applies (and the people who are Tahor may bring the Korban b'Tum'ah) even when the people who are Tamei do not bring the Korban at that time. If the reason why those who are Tahor must bring the Korban b'Tum'ah is in order not to disgrace those who are Tamei, this reason should apply only when those who are Tamei are actually bringing their Korbanos b'Tum'ah. (NODA B'YEHUDAH OC 2:86)
ANSWERS:
(a) When Rav discusses the principle of "Ein Korban Tzibur Chaluk," he does not refer to the same concept that Rebbi Yehudah teaches. Rebbi Yehudah maintains that "Ein Korban Tzibur Chaluk" simply allows everyone to bring the Korban b'Tum'ah when part of the Tzibur is permitted to bring it b'Tum'ah.
Rav, however, refers to a different type of "Ein Korban Tzibur Chaluk." His principle is not a Halachah d'Oraisa, but rather a Gezeirah d'Rabanan that was instituted for the explicit purpose of avoiding disgrace to others. Hence, Rav is saying that if there is a Tana who agrees with the Tana Kama, then according to that Tana, when half of the people are Tamei and half are Tahor, each group should bring their Korbanos separately. However, if that Tana also agrees that the principle of "Ein Korban Tzibur Chaluk" was instituted in order to prevent disgrace (that is, he agrees with the statement that Rebbi Yehudah expressed but for a completely different reason), then he requires that we make one more person Tamei so that everyone will bring the Korban b'Tum'ah.
When Rav says that this theoretical Tana agrees with Rebbi Yehudah, he merely means that the Tana follows a similarly-worded principle of "Ein Korban Tzibur Chaluk," but he does not agree with the reasoning of Rebbi Yehudah. This approach explains why Rashi explains the principle of "Ein Korban Tzibur Chaluk" in two different ways -- there are two different principles by that name.
(We may ask, though, why does the Gemara refer to the words, "Ein Korban Tzibur Chaluk," as Rebbi Yehudah's statement, rather than the Tana Kama's? The Tana Kama uses the same words (but in a situation in which a majority of the people are Tamei). The DIKDUKEI SOFRIM points out that in many manuscripts of the Gemara, in the text of Rabeinu Chananel, and in the text of the Yalkut, the words "Ein Korban Tzibur Chaluk" do not appear in the Tana Kama's statement.)
(b) RABEINU CHANANEL suggests an entirely different approach to the Gemara. He explains that the Gemara's conclusion is that Rav's ruling (that we must make one person Tamei) applies if there is a Tana who agrees with either the Tana Kama or Rebbi Yehudah. If there is a Tana who follows either ruling, then in a case in which half of the people are Tamei and half are Tahor according to Rebbi Yehudah (who maintains that everyone may bring the Korban b'Tum'ah), or in a case in which there is one more Tamei person than there are Tahor people according to the Tana Kama (who maintains that the Tamei people become a majority and everyone may bring b'Tum'ah), that Tana will be stringent and require a majority of two or more Tamei people, in order to satisfy the view of Rebbi Eliezer ben Masya. Although the Korban may be brought b'Tum'ah under those conditions according to each respective opinion, nevertheless we should be stringent. Therefore, we must be Metamei one of the Tahor people so that everyone may bring the Korban b'Tum'ah, even according to Rebbi Eliezer ben Masya.
According to Rabeinu Chananel, Rav is not discussing a theoretical Tana who holds like both the Tana Kama and Rebbi Yehudah, and therefore his approach avoids the question altogether.

80b----------------------------------------80b

2) "RITZUY TZITZ" FOR "TUM'AS HA'GUF"
QUESTION: The Mishnah states that the Tzitz is not Meratzeh for Tum'as ha'Guf (Tum'ah of the person who offers the Korban, in contrast to Tum'ah of the animal or its blood, or Tum'ah of the utensils used for offering the Korban).
The Gemara earlier (77a) teaches that if Tum'ah is "Dechuyah" b'Tzibur, the laws of Tum'ah are suspended because the Tzitz is Meratzeh. The Mishnah (79a) states that when the Tzibur or the Kohanim are Tamei, then "Tum'ah Dechuyah b'Tzibur" applies and the Korban may be brought b'Tum'ah. How can the principle of "Tum'ah Dechuyah b'Tzibur" apply in such cases, if there is no Ritzuy Tzitz for Tum'as ha'Guf?
ANSWERS:
(a) TOSFOS in Menachos (15a, DH v'Hacha) answers that Ritzuy Tzitz is needed only when it will work. Thus, Ritzuy Tzitz is necessary when the flesh of the Korban is Tamei, because Ritzuy Tzitz is effective for the flesh. When the Tzitz does not work, such as for Tum'as ha'Guf, Ritzuy Tzitz it is not needed.
This explanation needs clarification. The Gemara earlier (78a) states that according to the opinion that the Tzitz is not Meratzeh for items that are eaten ("Ein ha'Tzitz Meratzeh Al Achilos"), the principle of "Tum'ah Dechuyah b'Tzibur" does not cause the Tum'ah of the flesh of a Korban to be pushed aside to permit the Korban to be offered. According to that opinion, Tum'as Basar (the Tum'ah of edible meat of the Korban) is equivalent to Tum'as ha'Guf, in that the Tzitz is not Meratzeh for it. However, according to Tosfos, since the Tzitz is not Meratzeh for Tum'as Basar, that Tum'ah should be Dechuyah b'Tzibur even without the Tzitz!
Tosfos must mean that when the Tzitz works to be Meratzeh for the category of Nikravin (items offered as part of the Korban), Ritzuy Tzitz is required in order to offer any part of the Korban included in that category. Since the Tzitz is Meratzeh for Nikravin such as the blood of the Korban, every part of the Korban which is offered requires Ritzuy Tzitz in order to be brought b'Tum'ah, even those parts for which the Tzitz is not Meratzeh (such as the Basar).
The Tzitz does not work at all, though, for the category of Makrivin (those who offer the Korban). Since it does not work for them, they do not need it. The principle of "Tum'ah Dechuyah b'Tzibur" alone suffices to permit them to offer the Korban b'Tum'ah.
(b) The RAMBAM (Hilchos Bi'as ha'Mikdash 4:7) explains that when Tum'ah is Dechuyah b'Tzibur, the combination of the Tzibur and the Tzitz serves to be Meratzeh for Tum'as ha'Guf. According to the Rambam, the Tzitz indeed provides Ritzuy even for Tum'as ha'Guf in this case.
The CHAZON YECHEZKEL points out that the Rambam's source is the Gemara earlier (78a) which says that even though the Tzitz is not Meratzeh for Achilos (edible parts of the Korban) according to Rebbi Yehoshua, Rebbi Yehoshua permits a Korban Tzibur to be offered and eaten b'Tum'ah. The Rambam explains that this is because the Tzitz serves to be Meratzeh for the Achilah of a Korban Tzibur. (See the LECHEM MISHNEH, end of Hilchos Pesulei ha'Mukdashin 1:34, who discusses the Gemara on 78a according to the Rambam's opinion.)

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