1) ONE "TIGLACHAS" FOR TWO OBLIGATIONS
QUESTION: Rav Chisda rules that if a Nazir becomes a Metzora during his Nezirus, the days of his Tzara'as count towards his days of Nezirus. However, after he becomes Tahor from his Tzara'as (which involves shaving his hair on two different occasions -- once when he begins to count the seven days before he may bring his Korbanos to become Tahor, and once at the end of the seven days), he must wait thirty days before he brings the Korbenos Taharah for his Nezirus because he must grow his hair back in order to perform Tiglachas for his Nezirus.
The Gemara disproves Rav Chisda's opinion from a Beraisa. The Beraisa teaches that when a person accepts Nezirus for one year and then becomes a Safek Metzora and a Safek Nazir Tamei, he may eat Kodshim after two years have passed and he may drink wine only after four years have passed -- after all of the doubts involved with his status have been appropriately addressed (see Chart). According to Rav Chisda, this person should be permitted to drink wine after three years and thirty days, because after two years he definitely is no longer a Metzora and he may bring his Korbenos Nezirus, whether he was a Nazir Tamei or a Nazir Tahor: if he was a Nazir Tahor, he needs to wait only thirty days (in order to grow his hair) and then performs the Tiglachas of Nezirus. Since he might have been a Nazir Tamei, however, he needs to observe in Taharah the full period of Nezirus which he accepted (one year). Hence, after thirty days have passed he shaves (either as a Nazir Tahor or for the Tiglachas of a Nazir Tamei) and begins to count his one-year Nezirus, which is completed after a total of three years and thirty days have passed. Since the Beraisa says that he must wait four years, it must be that the days of his Tzara'as do not count towards the days of his Nezirus, and hence he must begin to count his Nezirus anew after he becomes Tahor from Tzara'as.
Before the Gemara cites the Beraisa, it cites a Mishnah (59b) which discusses an identical case of a Nazir Stam (a Nazir for thirty days), in which the Nazir may drink wine after 120 days have passed. However, the Gemara does not find sufficient proof in that Mishnah to disprove Rav Chisda's opinion, since even according to Rav Chisda the Nazir must wait thirty days after his Tzara'as in order to grow back his hair.
Why is the Gemara unable to disprove Rav Chisda's opinion from that Mishnah? If the days of Tzara'as count towards the days of Nezirus, the person should be permitted to drink wine after only sixty days! After the first thirty days, when he performs the first Tiglachas of Metzora mi'Safek, he should make a condition and say, "If I am a Metzora and I am Tamei, I want this Tiglachas to serve as my Tiglachas of Nazir Tamei and as my Tiglachas of Metzora." After sixty days, he should say, "If I am a Metzora, I want this Tiglachas to serve not only as my second Tiglachas of Metzora, but also as my Tiglachas of Nazir Tahor, since by now I am certainly a Nazir Tahor and the days of my Tzara'as count towards my Nezirus." He should not be required to count another thirty days in order to grow his hair back, since the second Tiglachas of Metzora itself was a valid Tiglachas of Nezirus Taharah! TOSFOS (DH Ochel) addresses this point and writes simply that the Tiglachas of a Metzora cannot count as a Tiglachas for a Nazir Tahor. Why not?
A similar question may be asked on the way Rav Chisda interprets the Mishnah here. According to Rav Chisda, the Mishnah means that if a Nazir accepts a thirty-day Nezirus, the days during which he was a Metzora do not count towards the days of his Nezirus since he must observe thirty days of growing his hair. Why must he make up days of growing his hair? He should simply wait thirty days before he performs the Tiglachas of Metzora, and he should perform one Tiglachas for both the Tzara'as and the Nezirus!
ANSWER: The Gemara later (60b) quotes Rebbi Shimon bar Yochai who explains that a Tiglachas cannot count for two different purposes. If it is a Tiglachas of a Metzora, it cannot serve also as a Tiglachas of Nezirus. Therefore, the first two Tiglachos must be for the Tzara'as exclusively, and then another two Tiglachos are necessary for Nazir Tamei and Nazir Tahor. (There is another reason why the Tiglachas of Metzora cannot count as a Tiglachas for Nazir Tamei: Tosfos writes that a person who is Tamei with Tum'as Mes cannot become Tahor while he is a Metzora (during the days of his Chaluto or even during the seven days between his two Tiglachos; see Insights to 60b). Accordingly, Tosfos addresses only the possibility of using the Tiglachas of a Metzora for the Tiglachas of a Nazir Tahor.)
Similarly, in the case of the Mishnah, the Nazir's Tiglachas of Tzara'as cannot count as his Tiglachas of Nezirus. (He cannot shave for his Nezirus before he shaves for his Tzara'as, because a Metzora is prohibited from shaving. See Moed Katan 15a, and RAMBAM, Hilchos Tzara'as 10:6.)
(The TOSFOS CHITZONIYOS cited by the SHITAH MEKUBETZES writes that the Gemara indeed could have disproved Rav Chisda's opinion from the case of the thirty-day Nezirus (which must be observed for 120 days). The only reason it chooses to disprove Rav Chisda's opinion from the Beraisa which discusses the one-year Nezirus is that the Gemara concluded that the Mishnah refers to a Nezirus Merubah (a Nezirus longer than thirty days) according to Rav Chisda. The intention of the Tosfos Chitzoniyos is not clear, because even according to Rav Chisda one Tiglachas cannot count for two different purposes, as the Tosfos Chitzoniyos himself writes earlier.)

56b----------------------------------------56b

2) OMITTING A SOURCE IN THE CHAIN OF TRADITION
QUESTION: The Gemara teaches that when one quotes a teaching which has been passed down through a long line of Tana'im, one must quote only the first and last sources and not the middle source (or sources). Rav Nachman proves this from the Mishnah in Pe'ah (2:6) in which Nachum ha'Lavlar related a certain teaching he "received as a tradition from Rebbi Mei'asha, who received it from 'father,' who received it from the 'Zugos,' who received it from the Nevi'im, who received it as a Halachah l'Moshe mi'Sinai." Nachum ha'Lavlar's omission of Yehoshua and Kalev from the list of sources shows that one is not required to list the middle sources.
If one is not required to mention the middle sources, why did Nachum ha'Lavlar mention all of the other sources between Rebbi Mei'asha and Moshe Rabeinu?
ANSWERS:
(a) The CHIDA in PESACH EINAYIM answers that the Gemara does not mean that one should omit the middle sources, but rather that one is permitted to omit the middle sources. The Gemara often quotes a statement in the name of a long list of Amora'im or Tana'im (and not simply in the name of the first source and last source). The ARZEI HA'LEVANON points out that this is also implied by the words of the ROSH here.
Why, though, would a Tana such as Nachum ha'Lavlar choose to list some names and omit others?
Perhaps the answer is as follows. The reason why one should mention any earlier sources when he relates a teaching is the principle, "One who relates a teaching in the name of the one who originally said it brings redemption to the world" ("Mevi Ge'ulah l'Olam"; Megilah 15a). The Gemara here seeks to prove that even when one knows the entire chain of sources but has a reason to omit some names, he is permitted to omit them (and he does not impede the Ge'ulah). Nachum ha'Lavlar did not need to mention Yehoshua and Kalev because everyone knows the chain of Kabalah between Moshe Rabeinu and the Nevi'im, as the Mishnah in Avos (1:1) teaches, "Moshe taught the Torah to Yehoshua who taught it to the Zekenim who taught it to the Nevi'im." (Kalev is included in the "Zekenim," because he apparently was the leading elder of the Zekenim, and perhaps the oldest, as he was one of the only survivors of the sojourn in the Midbar). Nachum ha'Lavlar's omission of those two sources does not impede the Ge'ulah because their names are known without having to mention them. (See Insights to Nidah 19:2.)
Similarly, in the Mishnah here, Rebbi Yehudah -- who quotes the teaching of Rebbi Eliezer -- does not detract from the Ge'ulah by not quoting all of the sources, since the statement was already known to have been said by Rebbi Eliezer. Rebbi includes the entire chain of tradition in a Mishnah only when he quotes a Tana's words with the exact wording that the Tana himself used (in first person, such as the words of Nachum ha'Lavlar who said, "I received a from...").
(b) The MEFARESH explains that Nachum ha'Lavlar quoted everyone from the Nevi'im and onward because they are all considered one single unit in the chain of tradition, since they all lived during the times of the second Beis ha'Mikdash and onward. Apparently, the Mefaresh understands that one must mention all of the people in the chain of tradition who lived in the same time period as the last (or first) link. Perhaps the reason why the Mishnah omits mention of Rebbi Yehoshua ben Mamal is that he lived during the time of the second Beis ha'Mikdash, while Rebbi Eliezer taught after the Churban (see Gitin 56a).

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