1) IMMERSING VESSELS IN A MIKVAH ON YOM TOV
QUESTIONS: The Mishnah (17b) states that both Beis Shamai and Beis Hillel agree that one may not immerse Kelim in a Mikvah on Yom Tov. The Gemara records four different reasons for the prohibition: one might carry the Kelim four Amos in Reshus ha'Rabim on Shabbos (Rabah); one might squeeze (Sechitah) the water out of clothing that required immersion (Rav Yosef); one might delay (Shema Yeshaheh) immersing his Kelim until Yom Tov and then forget and use them for Terumah (Rav Bivi); it appears that he is repairing a utensil (Nir'eh k'Metaken Kli) when he immerses it (Rava).
The Gemara questions Rabah's reason from a number of Beraisos, and it resolves those questions. One Beraisa says that a person is permitted to draw water from a well on Yom Tov with a bucket which is Tamei, even though the bucket will become Tahor as a result. Another Beraisa permits one to immerse a Kli which is Tamei from a Velad ha'Tum'ah.
RASHI explains why the Tevilah is permitted in both cases: since the reason for the prohibition of Tevilah on Yom Tov is because it appears as though one is repairing the Kli, in these cases it does not appear as though one is repairing a Kli and thus the prohibition does not apply. In the case of drawing water with a Tamei bucket, one performs an act of drawing water and not an act of immersing a Kli (even though the Kli becomes Tahor as a result, it does not appear as though he is fixing the Kli) (RASHI DH b'Deli Tamei). When one immerses a Kli that is Tamei with Velad ha'Tum'ah, it does not appear as though he is repairing the Kli because the Tum'ah is only mid'Rabanan (RASHI DH b'Velad ha'Tum'ah).
Similarly, the Gemara cites a Beraisa which states that a woman may immerse herself in a Mikvah on Yom Tov while she is wearing her clothes even though the clothes will become Tahor as a result. RASHI there (DH Ma'aremes) also explains that she is permitted to immerse with her clothes because the act does not look like an act of fixing a Kli, since she immerses her entire body.
Rashi's explanation is difficult to understand. The Gemara at this point is explaining Rabah's reason for the prohibition of Tevilah on Yom Tov. Rabah says that Tevilah is prohibited on Yom Tov because one might carry the object in Reshus ha'Rabim on Shabbos. Why, then, does Rashi mention the reason mentioned later in the Gemara (in the name of Rava), that Tevilah is prohibited on Yom Tov because of "Nir'eh k'Metaken Kli," it appears as though one is fixing a Kli? (TOSFOS YESHANIM cited by MAHARSHA, and RASHBA)
Second, if the reason for the prohibition is because one might carry in Reshus ha'Rabim, then why does the Beraisa permit one to draw water with a Tamei bucket or to immerse a Kli that is Tamei with Velad ha'Tum'ah? Why does the Beraisa permit a Nidah to immerse while wearing clothes? The concern that one might carry in Reshus ha'Rabim -- as well as the other two concerns (Sechitah and Shema Yeshaheh) -- also should apply in these cases. However, when the Gemara asks that Tevilah in these cases should be prohibited, it does not ask that Tevilah should be prohibited because one might carry the object in Reshus ha'Rabim, but rather it asks that Tevilah should be prohibited for different reasons (in the case of the bucket, one might immerse the bucket by itself without drawing water; in the case of the Velad ha'Tum'ah, one might permit immersing a Kli that is Tamei with Av ha'Tum'ah; in the case of the Nidah, she might immerse the clothing by itself while she is not wearing it). Why does the Gemara not ask that those cases should be prohibited because one might carry the objects in Reshus ha'Rabim (or, according to Rav Yosef, because one might squeeze water out of them, or, according to Rav Bivi, because one might delay immersing them until Yom Tov)? (MAHARSHA, PNEI YEHOSHUA)
Similarly, why does the Mishnah permit one to perform Hashakah with water, or to immerse "mi'Gav l'Gav" (a Tevilah done for extra cautiousness)? It is true that the reason of Metaken Kli does not apply in these cases (since Hashakah does not "fix" the water but "plants" it, and since "mi'Gav l'Gav" is not required but is only an extra measure of cautiousness). However, the reasons given by Rabah, Rav Yosef, and Rav Bivi should prohibit the Tevilah even in those cases. (TOSFOS DH NIGZAR)
ANSWERS:
(a) TOSFOS does not mention the problem of Metaken Kli with regard to these cases at this stage in the Gemara. Furthermore, he establishes a logical reason for why the other Gezeiros do not apply to these cases.
Tosfos addresses the question of why Hashakah with water is permitted and there is no concern that one will carry the water in Reshus ha'Rabim (according to Rabah). Tosfos writes that since a person has other water to drink, he is not pressured to do Hashakah with the Tamei water and therefore he will not forget and carry the water in Reshus ha'Rabim. (The other reasons -- Sechitah and Shema Yeshaheh -- also do not apply: there obviously is no problem of Sechitah since Hashakah is done only with water and not with a Kli. Similarly, Shema Yeshaheh applies only to pots and utensils which one might accidentally use with Terumah (and thereby cause Terumah to become Tamei) before he immerses them.)
The same approach explains the case of "Tevilah mi'Gav l'Gav": since one is not so pressured to immerse the Kelim (because they are Tahor already) there is no fear that he will forget and carry the Kelim in Reshus ha'Rabim. (Shema Yeshaheh does not apply to these Kelim. Since they are really Tahor, even if he accidentally uses them for Terumah the Terumah will remain Tahor. Similarly, the Gezeirah of Sechitah does not apply to Kelim which one immerses "mi'Gav l'Gav," because he does not need to immerse them and thus he will not squeeze them out afterwards. In contrast, when one immerses Kelim which need Tevilah because they are Tamei and are needed for Terumah, he will be so concerned that he have Kelim available for use that he might inadvertently squeeze them out after he immerses them.)
With regard to the case in which one immerses a Tamei bucket while he draws water with it, and the case of a Nidah who immerses with her clothing, it is obvious why there is no concern that one will carry the item in Reshus ha'Rabim. The bucket hangs next to the well and one does not remove it from its place there (MAHARSHA). The woman wears the clothes with which she immerses, and thus there is no fear that she will carry them. (The Rabanan did not make a Gezeirah to prohibit Tevilah in those cases lest one immerse a bucket that is not hanging next to the well, and lest a woman remove her clothes and then immerse, because of the reasons the Gemara gives.)
The MAHARSHA suggests that this is the opinion of Rashi as well. Why does Rashi mention that the reason why the Tevilah in these cases is permitted is because there is no concern that the act appears as though one is fixing a Kli? The Maharsha answers that Rashi chooses to mention Rava's reason to explain these Beraisos merely because his is the final reason given in the Gemara. (Rashi earlier (17b, DH ha'Matbil) mentions that reason as the standard reason for why Tevilas Kelim is prohibited on Yom Tov.) Even though the Gemara at this stage does not know that reason, Rashi explains the reason of the Beraisos according to the conclusion of the Gemara, and it is understood that there will be no question as to why those cases are permitted according to the other opinions, for the reasons given by Tosfos.
(See also PNEI YEHOSHUA who suggests that Abaye, who discusses Rabah's reason when he cites the Beraisos which permit Tevilah on Yom Tov, agrees with Rava who says that the reason for the prohibition is because of Nir'eh k'Metaken Kli. Since this is how Abaye understands the Beraisos, Rashi mentions that reason at this stage of the Gemara.)
(b) Perhaps the second question above answers the first question. Rashi is bothered with why Hashakah, Tevilah mi'Gav l'Gav, and Tevilah of a Kli which is Tamei with Velad ha'Tum'ah are permitted, as well as why the other cases of Tevilah on Yom Tov are permitted. He does not accept Tosfos' explanation that the person is not pressured and therefore will not accidentally carry the Kli in Reshus ha'Rabim.
Rather, Rashi understands that Rabah maintains that the Gezeirah which prohibits Tevilah on Yom Tov applies only when there is a combination of two reasons to prohibit the Tevilah, but not when there is a single concern that one might carry in Reshus ha'Rabim. Therefore, whenever both concerns are present -- the concern that one might carry in Reshus ha'Rabim and the concern that it appears as though one is fixing a Kli -- the Gezeirah applies. The same is true for the other opinions (Rav Yosef and Rav Bivi); only when both the problem that one appears to be fixing a Kli and the problem of Sechitah or Shema Yeshaheh are present does the Gezeirah prohibit the Tevilah. When the problem of Nir'eh k'Metaken Kli is absent (such as in the case of the Tamei bucket, the Kli with Velad ha'Tum'ah, and the clothing of the Nidah), the Gezeirah does not apply, even though one other concern (such as carrying the item in Reshus ha'Rabim) remains.
However, if it is true that Rabah, Rav Yosef, and Rav Bivi agree that the problem of Nir'eh k'Metaken Kli is also a concern, then why do they say that the Gezeirah applies only when there is a second concern? Why do they reject Rava's suggestion that the Gezeirah applies even when the single concern of Nir'eh k'Metaken Kli is present?
The answer is that the Gemara found a fault with Rava's reason of Nir'eh k'Metaken Kli. The Gemara asks that if the basis for prohibiting Tevilah on Yom Tov is the concern that one appears as though he is fixing a Kli, then a man should also be prohibited from immersing himself on Yom Tov, Shabbos, and Yom Kippur. However, the Mishnah clearly permits a man to immerse. The Gemara suggests an answer for Rava, but the other opinions do not accept the answer and instead give different approaches to this question. Rabah, Rav Yosef, and Rav Bivi suggest that the Rabanan enacted the Gezeirah of Nir'eh k'Metaken Kli only when there is an additional reason to prohibit the Tevilah (such as the concern that one might carry the Kelim in Reshus ha'Rabim, or Sechitah, or Shema Yeshaheh). None of these additional reasons exist in the case of Tevilah of a man (the Rabanan were not concerned for Sechitah of a man's hair, see Shabbos 40b; Shema Yeshaheh does not apply to a man, because a person does not delay his Tevilah but rather immerses right away when he becomes Tamei in order to be able to eat Terumah (or to eat Chulin in a state of Taharah), as Tosfos explains in DH Gezeirah). Therefore, a person is permitted to immerse on Yom Tov. As mentioned above, the other cases are permitted because one of the two reasons for the Gezeirah is absent -- there is no concern of Nir'eh k'Metaken Kli. (M. KORNFELD)
2) IMMERSING A UTENSIL WHICH IS TAMEI WITH AV HA'TUM'AH ON YOM TOV
QUESTION: The Gemara says that on Yom Tov one may immerse a Kli that is Tamei even with Av ha'Tum'ah if it became Tamei on Yom Tov (RASHI).
Why is the Tevilah of such a Kli permitted? It should be prohibited because the act of Tevilah appears like an act of fixing a Kli (Nir'eh k'Metaken Kli), or because of any of the other reasons mentioned in the Gemara earlier (one might carry the Kli four Amos in Reshus ha'Rabim on Shabbos; one might squeeze (Sechitah) the water out of clothing that required immersion; one might delay (Shema Yeshaheh) immersing his Kli until Yom Tov and then forget and use it for Terumah).
ANSWERS:
(a) The MAHARSHA explains that the Rabanan prohibited Tevilah on Yom Tov only when there is an alternative course of action. If one could have immersed the Kli before Yom Tov, then the Gezeirah applies and prohibits him from immersing the Kli on Yom Tov. In this case, however, there was no option to immerse the Kli before Yom Tov, because it became Tamei only on Yom Tov. In such a case, the Rabanan did not apply the Gezeirah.
REBBI AKIVA EIGER challenges the Maharsha's explanation. If the Rabanan did not apply their Gezeirah when the Kli became Tamei on Yom Tov because the person has no other option, then why does the Gemara ask that the Tevilah should be prohibited lest one immerse a Kli that became Tamei before Yom Tov? If the Rabanan did not apply the primary Gezeirah (to prevent one from carrying the Kli in Reshus ha'Rabim on Shabbos) when a Kli becomes Tamei on Yom Tov since there is no other option, then certainly they should not apply a secondary Gezeirah (to prevent the Kli from being confused with a Kli that became Tamei before Yom Tov) to prohibit the Tevilah of a Kli that became Tamei on Yom Tov.
(b) The CHOCHMAS MANO'ACH points out that the requirement of "He'erev Shemesh" teaches that a Kli immersed on Yom Tov may not be used for Terumah on the same day, because Terumah requires not only that the Kli be immersed but that the entire day pass as well ("He'erev Shemesh"). For what purpose, then, does one immerse a Kli on Yom Tov? It must be that he intends to use the Kli for non-Terumah items (Chulin), as Rashi says. There is no prohibition against using a Tamei Kli for Chulin; it is merely a stringency (Chumra) of the Rabanan that one should eat Chulin in a state of Taharah. Since it is only a Chumra, the Tevilah of the Kli does not appear like an act of fixing the Kli (just as it does not appear like an act of fixing a Kli when one immerses a Kli which is Tamei with Velad ha'Tum'ah, as Rashi explains).

18b----------------------------------------18b

3) HALACHAH: IMMERSING IN THE MIKVAH ON TISH'AH B'AV AND YOM KIPPUR
OPINIONS: The Beraisa states that one who is obligated to immerse in a Mikvah may immerse in the usual manner even on Tish'ah b'Av and on Yom Kippur.
In practice, is a woman permitted to immerse on those days if the time of her Tevilas Mitzvah falls then?
(a) TOSFOS (18b, DH Kol) explains that all of the Tevilos performed nowadays are not considered to be "in their proper time." A woman does not follow the exact schedule of counting days as prescribed by the Torah; rather, she is much more stringent and adds days in order to prevent any mishap that might arise from a miscalculation. Consequently, a woman's Tevilas Mitzvah never occurs at the Torah-prescribed time, and thus she may not immerse on Tish'ah b'Av or Yom Kippur. Only when Tevilah was performed at the Torah-prescribed time was a woman permitted to immerse on those days because of the "Mitzvah to perform Tevilah in its proper time" (Beitzah 18b).
(b) Tosfos cites RABEINU TAM who says that the Halachah follows the opinion that immersion at the proper time is not a Mitzvah (and thus it may be delayed). According to that opinion, it was never permitted to perform Tevilah on Tish'ah b'Av or Yom Kippur.
(c) TOSFOS in Shabbos (111a, DH Lo) cites the RI who explains that a woman is permitted to immerse at the proper time, even on Tish'ah b'Av and Yom Kippur, only in order to permit her to handle and to eat Taharos but not in order to permit her to her husband. Nowadays we do not immerse for Taharos, and thus a woman is not permitted to immerse on Tish'ah b'Av or Yom Kippur. (The concession to immerse for Taharos was made due to a pressing concern that one who is Tamei might come into contact with Taharos right away and be Metamei them. Immersion for the sake of resuming marital relations is not immediately necessary, because marital relations are forbidden on Tish'ah b'Av and Yom Kippur.)
(d) TOSFOS in Shabbos (111a, DH Tovlin) cites the Gemara in Ta'anis (13a) which says in the name of Rebbi Chanina Segan ha'Kohanim that even if Tevilah in its proper time is a Mitzvah, it is not proper to perform Tevilah on Tish'ah b'Av because "it is worthwhile to lose a day of Tevilah once a year in mourning over the Beis ha'Mikdash." The Yerushalmi rules like Rebbi Chanina Segan ha'Kohanim.
HALACHAH: The SHULCHAN ARUCH (OC 554:8 and 613:12) rules that a woman may not immerse in a Mikvah on Tish'ah b'Av or Yom Kippur because of the first reason mentioned above: Tevilos nowadays are not considered to be in their proper time. (See also Insights to Shabbos 111:1.)

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