1) WHEN MUST "CHAFIFAH" BE PERFORMED?
OPINIONS: The Gemara says that the Halachah is that a woman must perform Chafifah (cleaning before immersing in a Mikvah) during the day. It then says that the Halachah is that a woman must perform Chafifah only at night. The Gemara resolves the contradiction by saying that one statement refers to "when it is possible" and the other refers to "when it is not possible." What does the Gemara mean with this answer?
(a) RASHI (DH Ha d'Efshar and DH Ha d'Lo Efshar) explains that "when it is possible" refers to the first Halachic statement. It means that when the day before her immersion is a weekday, she should perform Chafifah during the day. "When it is not possible" refers to the second statement. It means that when the night of her immersion falls on Motza'i Shabbos and it is not possible to perform Chafifah during the day on Shabbos, she should perform Chafifah at night before she immerses. Normally, though, it is better to perform Chafifah during the day.
(b) TOSFOS (DH Kach Amru) cites the SHE'ILTOS who explains that "when it is possible" refers to the second statement. It means when the night of her immersion falls on an ordinary weekday and it is possible to perform Chafifah at night, she should do Chafifah at night immediately prior to immersing, since it is always better to perform Chafifah at night.
(c) Tosfos cites RABEINU TAM who understands that the Gemara is not discussing a normal case of Tevilah on a weeknight. Rather, both Halachic statements refer to when the night of the immersion is a Motza'i Shabbos. "When it is possible" means when it is possible to perform Chafifah that night (such as when Motza'i Shabbos is a weeknight and not a Yom Tov), and it refers to the second statement. "When it is not possible" refers to the first statement, and it means that when Motza'i Shabbos is a Yom Tov and it is impossible to perform Chafifah on Motza'i Shabbos, she performs Chafifah during the day -- on Erev Shabbos, even though it is more than an entire day before the Tevilah.
(d) The SHACH (YD 199:6) has a novel interpretation of Rashi's words. The Shach explains that the phrase "when it is not possible" refers to the second statement, and it means that in a case in which there would be a three-day delay if she would perform Chafifah during the day, she is to perform Chafifah on Motza'i Shabbos. (For example, the time for her immersion occurs on Monday night. Sunday and Monday are Rosh Hashanah. The only time she would be able to perform Chafifah during the day would be on Friday, but Friday is too far away from the time of her immersion.) "When it is possible" refers to a normal case, when she immerses on a weeknight. In such a case she should perform Chafifah during the day.
HALACHAH: The SHULCHAN ARUCH (YD 199:3) writes that a woman should conduct herself as Tosfos recommends, beginning her Chafifah during the day and continuing it into the night, and in that way she satisfies all of the above-mentioned opinions.
The REMA adds that b'Di'eved, when necessary, a woman may perform Chafifah either exclusively during the day or exclusively at night. (The Shach concludes that the most correct opinion is that of Rashi (according to his own understanding of Rashi), that the Chafifah should be performed during the day under normal circumstances.)
When the night of her immersion is Motza'i Shabbos, the logical ruling would be to follow all of the interpretations of the Rishonim mentioned above, and she should perform Chafifah at night on Motza'i Shabbos. This is the ruling of the Shulchan Aruch (YD 199:4). The Rema, however, quotes the TUR who says that it is best to perform a complete Chafifah on Erev Shabbos, and to do a small Chafifah on Motza'i Shabbos as well. (Perhaps the Tur comes to this conclusion because he understands the words of Rashi as the Shach does.)
68b----------------------------------------68b
2) WHEN DOES A "NAZIR" BECOME "TAMEI"?
QUESTION: The Mishnah discusses a case in which a Zav (whose flow of Zivah has ceased and now he must count seven days of Taharah) examined himself only on the first and seventh days and found himself Tahor, but he did not examine himself on the other days. According to Rebbi Eliezer, he is assumed to be Tahor. According to Rebbi Yehoshua, he is considered as though he counted only two Tahor days, and he must count another five Tahor days in order to attain seven days of Taharah. (See BARTENURA.)
The Gemara cites a Beraisa in which Rebbi Eliezer said to Rebbi Yehoshua that according to his view that the two days on which he examined himself are counted towards the seven days of Taharah, counting non-consecutive days suffices for the seven days of Taharah. However, this contradicts the Torah's statement that the Zavah must count seven days in order to become Tahor, which teaches that there must be no days of Tum'ah that interrupt the Tahor days (see Rashi to 33b, DH Tistor). Rebbi Yehoshua answered that even Rebbi Eliezer must agree that a Nazir -- who is not permitted to become Tamei through contact with a Mes or being in the same room as a Mes -- who entered "Sechachos" or "Pera'os" loses from his count the day on which he went to that place. ("Sechachos" and "Pera'os" are areas about which there is a doubt whether they have the status of an Ohel. The Gemara earlier (57a) describes "Sechachos" as a tree that covers a place where there is known to be a grave but it is not known under which branch it is located. "Pera'os" are large stones that jut out from a fence, and a Mes is buried beneath one of them but it is not known under which one.) Nevertheless, he may include the days before and after in order to reach the number of days (30) necessary to complete his Nezirus. This law clearly implies that one may count even non-consecutive days.
The Gemara says that Rebbi Eliezer rejected this argument because the Nazir is Tamei mid'Oraisa only when he certainly was under the same roof (Ohel) as the Mes. In contrast, in the cases of Sechachos and Pera'os, there is only a doubt about whether he was in the Ohel of a Mes, and thus the prohibition against entering those areas is only mid'Rabanan. No one will confuse this Isur d'Rabanan with the Isur d'Oraisa, and thus in this case it is not necessary to count seven consecutive days.
RASHI (DH Ohel) explains that a Nazir becomes Tamei mid'Oraisa only when he definitely enters the Ohel of a Mes, as the Torah says, "... when one dies next to him (Alav)" (Bamidbar 6:9). This teaches that he is Tamei only when the Tum'ah is "Mechuveres" -- clear and beyond a doubt, as the Gemara in Pesachim (81b) explains.
Rashi's statement here, however, seems inconsistent with the Gemara in Pesachim. The Gemara there discusses specifically the Tum'ah of Tum'as ha'Tehom. Tum'as ha'Tehom refers to Tum'ah that was unknown or hidden, such as a corpse that was discovered lying beneath a road. If a Nazir became Tamei through Tum'as ha'Tehom before he offered his Korbenos Nazir but only afterwards found out about his Tum'ah, he does not need to bring his Korbanos again. This law is a Halachah l'Moshe mi'Sinai and is not derived from the verse of "Alav." In contrast, in the cases of Sechachos and Pera'os, we know for certain that there is a Mes in the area, but we do not know whether the Nazir was in the same Ohel as the Mes. How can Rashi compare the Gemara here, which discusses Sechachos and Pera'os, where there is a doubt about whether the Nazir passed over the Mes, to the Gemara in Pesachim, which discusses Tum'as ha'Tehom? Tum'as ha'Tehom is a special Halachah l'Moshe mi'Sinai that teaches that even when it is known for certain that the Nazir passed over a corpse, the Nezirus is not invalidated because no one in the world was aware of the Mes. (See RAV SIMCHAH MI'DESVEI.)
ANSWER: The TESHUVOS ACHI'EZER (1:34:1, DH v'Rashi) answers that Rashi's source is the Sifri (Bamidbar 6:9) which states that the word "Alav" teaches that even a Nazir who was forced to have contact with a Mes is required to begin his count again. The Sifri derives from the verse that even though the status of a Nazir whose Tum'ah is in doubt is not the same as the status of a Nazir who certainly became Tamei, the status of a Nazir who was forced to become Tamei is the same as the status of one who willfully became Tamei. The Achi'ezer explains that the Sifri is clearly not discussing Tum'as ha'Tehom, because in the case of Tum'as ha'Tehom even when a Mes was certainly present the Nazir remains Tahor if no one knew about the Mes. The Sifri is saying that even when there is a Safek in Reshus ha'Yachid, the Nazir remains Tahor and we do not apply the normal rule that states that a Safek Tum'ah in Reshus ha'Yachid is Tamei.
Rashi maintains that the Sechachos and Pera'os discussed here are not Metamei the Nazir with Tum'ah d'Oraisa even when they are in Reshus ha'Yachid. The Rabanan, however, decreed that the day on which the Nazir walked through the Sechachos and Pera'os cannot be counted towards his 30 days of Nezirus, but it does not force him to begin counting again from the beginning.
(According to this explanation, the reason why Rashi refers to the Gemara in Pesachim must be merely because the Gemara there mentions the concept that the Nazir is Tamei only when it is clear to him that he had contact with Tum'ah. Rashi is not referring to the specific Tum'ah of Tum'as ha'Tehom that the Gemara there discusses, but rather the normal Safek of Sechachos and Pera'os which the Gemara here discusses and to which the Sifri alludes.) (D. BLOOM)