1) CUTTING UP A "BECHOR" AS IT EXITS THE WOMB
QUESTIONS: Rav Huna and Rabah argue about when the sanctity of a firstborn calf takes effect. Rabah maintains that a firstborn calf becomes Kadosh as a Bechor only from the time that the majority of the calf exits the womb. Rav Huna maintains that a firstborn calf becomes Kadosh retroactively; once a majority of the calf is born, retroactively the entire calf becomes Kadosh.
The Gemara cites the Mishnah (69b) as proof for the view of Rabah. The Mishnah states that for an animal experiencing a difficult first birth, one may cut the fetus into pieces as each part exits the womb and throw them to the dogs. The pieces do not have the Kedushah of a Bechor. The Mishnah presumably refers even to a case in which all of the pieces of the fetus are still in front of us, and nevertheless it says that the fetus does not have Kedushah. This supports Rabah's view that the fetus becomes Kadosh only from the time that a majority exits.
(a) How does the Mishnah support Rabah's view? Rabah agrees that the calf becomes Kadosh from the time that a majority exits the womb. Once a majority of the pieces have exited, the remaining parts of the fetus should be Kadosh! Why does the Mishnah say that all of the parts may be thrown to the dogs?
(b) There is a more basic question that the Gemara should have asked on the view of Rav Huna. According to Rav Huna, one should not be permitted to cut the firstborn calf in the first place, since he thereby maims an animal of Kodshim! Why does the Gemara not ask this question?
ANSWERS:
(a) TOSFOS (DH Mai) and RASHI (DH Mechatech) answer that the Mishnah indeed permits only the first half of the calf to be thrown to the dogs. Once a majority has exited the womb, the rest that exits is Kadosh and must be buried.
(b) Tosfos answers that the Gemara does not ask this question on Rav Huna, because perhaps the Mishnah is discussing a Bechor that is not fit to be offered on the Mizbe'ach (such as a stillborn), and thus it does not have the Kedushah of Kodshim, and one is permitted to maim such a Bechor. (Alternatively, the Mishnah may be referring to cutting up the animal before it exits the womb, which renders it a stillborn and unfit to be offered.)
2) WRAPPING A FIRSTBORN CALF IN "SIV" DURING ITS BIRTH
QUESTION: Rava asks what the Halachah would be in a case in which a firstborn calf was wrapped in "Siv" (tendril, or bast of a palm tree) during its birth in order to aid in its delivery. Does a calf born in this manner have the status of a Bechor? As RASHI (DH Mahu) explains, Rava's question is whether the Siv has the status of a "Chatzitzah" that intervenes between the calf and the walls of the womb so that this calf is not considered the "Peter Rechem," the birth that "opens the womb" (see Shemos 13:2), and thus does not have the Kedushah of a Bechor.
What is the difference between this case and the case in Pesachim (115b) of a person who wraps Matzah and Maror in Siv on Seder night and swallows it? The Gemara there rules that the person fulfills neither the Mitzvah of eating Matzah nor the Mitzvah of eating Maror, since the Siv acts as a Chatzitzah between the food and the person's mouth. Why, in that case, is it obvious that the Siv is a Chatzitzah, while Rava here is in doubt about whether a Siv is a Chatzitzah between the newborn calf and the walls of the womb? (See MAHARATZ CHAYOS.)
ANSWERS:
(a) The AVNEI NEZER (cited by RAV MOSHE FEINSTEIN zt'l in IGROS MOSHE YD 3:125) states that Rava's doubt is whether or not a Chatzitzah poses any problem for the Kedushah of a Bechor. That is, certainly the Siv is a Chatzitzah. However, perhaps a separation between the calf and the mother does not prevent the calf from becoming Kadosh as a Bechor.
In contrast, swallowing Matzah and Maror wrapped in Siv is problematic not because the Siv is a Chatzitzah between the food and the mouth, but because this is not the normal manner of eating (as the SHULCHAN ARUCH (OC 475:3) writes). It is not considered as though the person ate Matzah and Maror. As the RASHBAM in Pesachim (115b, DH Karchan) writes, it is equivalent to throwing a stone into a bottle. In contrast, facilitating a birth through the intervention of Siv is not considered a significant change in the birth process to prevent the calf from becoming Kadosh as a Bechor.
Rav Moshe Feinstein questions the Avnei Nezer's explanation. It is clear from the Gemara in Bechoros (9b) that in a case in which male twins were born, the only reason why the second calf is not considered a Chatzitzah between the first calf and the womb is that both calves are of the same "Min," and the rule is that "Min b'Mino Eino Chotzetz" -- the law of a Chatzitzah does not apply to two items of the same type. Rav Moshe Feinstein states that it is clear from the Gemara there that an object of a different substance ("Min b'Eino Mino") would be a Chatzitzah when the firstborn calf is born.
(b) RAV MOSHE FEINSTEIN (ibid.) writes that it is clear to Rava that in general a Chatzitzah between the newborn calf and the womb disqualifies the calf from having the Kedushah of a Bechor. However, Rava here is asking that since the wrapping of the calf in the Siv was for its own benefit, because it was a cold day and the Siv warmed it and prevented it from becoming sick, perhaps the wrapping does not constitute a Chatzitzah. Something done for the sake of the calf itself does not constitute a Chatzitzah.
Rav Moshe Feinstein states that according to this explanation, the continuation of the Gemara is easy to understand. The next question of Rava is what the Halachah would be in a case in which the calf was wrapped in a garment. Does this constitute a Chatzitzah between the calf and the womb? Rava means that even if the law is that a Siv is a Chatzitzah because it does not warm the calf well and therefore it does not provide a significant benefit to the calf such that it would not be considered a Chatzitzah, perhaps a piece of clothing that does warm the calf sufficiently is considered entirely for the benefit of the calf and is not a Chatzitzah. (D. BLOOM)
3) THE WEASEL IN THE WOMB
QUESTION: Rava asks what the Halachah would be in a case in which a weasel crawled into the womb of a cow, swallowed its fetus, exited the womb, re-entered the womb and vomited the fetus there, and then the fetus exited the womb on its own.
This case seems to be extremely farfetched. How could such a thing occur?
ANSWER: TOSFOS in Kesuvos (4b, DH Ad) writes that the Chachamim of the Gemara occasionally discuss theoretical situations that never could occur in reality. Their purpose in such discussions is to teach or establish a concept or logical point that is relevant in practice or that helps us to understand the Halachah better. Tosfos proves this from the Gemara here, which discusses a case that obviously is only theoretical.

70b----------------------------------------70b

4) A FETUS IS NOT "TUM'AH BELU'AH"
QUESTION: The Gemara seeks the source for the Halachah that a dead fetus inside the womb of an animal is not Metamei the person who reaches in and touches it.
There seems to be an obvious source for this Halachah. The Gemara later (71a) discusses the Halachah of "Tum'ah Belu'ah" (lit. "swallowed Tum'ah"), which refers to an object that is Tamei inside of a living creature. While the object is still inside, the object is not Metamei anything that touches or carries it. Why does the Gemara not mention this as the source for the Halachah that a dead fetus is not Metamei the person who touches it?
ANSWERS:
(a) RASHI (DH Kal va'Chomer) and TOSFOS (DH Mai) explain that the Gemara wants to find a source for this Halachah even according to Rebbi Akiva. Rebbi Akiva (72a) maintains that a human fetus does cause Tum'ah even though it is Belu'ah.
(b) Tosfos suggests another answer. The Gemara knows that there is a verse (as the Gemara later quotes to explain the view of Rebbi Yosi ha'Glili in the Mishnah) which implies that a dead fetus in an animal is Tamei. This verse would have been the source (according to the Tana Kama in the Mishnah) that a dead fetus inside of an animal is Tamei if not for the Kal va'Chomer that teaches that it is illogical to explain the verse in such a manner.
(c) The BA'AL HA'ME'OR explains that the Mishnah considers even a limb that protrudes from the womb to be Tahor. Such a limb is obviously not Tum'ah Belu'ah, since it has emerged from the womb. Therefore, the Gemara needs to find a different source that it is Tahor. (According to Tosfos later (72a, DH Gezeirah), this answer does not suffice. Tosfos says that it is precisely in such a case -- when a limb protrudes from the womb -- that Rebbi Yishmael considers the fetus Tahor and Rebbi Akiva considers it Tamei. Thus, the Sugya here must be following the opinion of Rebbi Akiva when it seeks a source that such a limb is Tamei, and we must return to the first answer (a) above.)
5) THE SOURCE THAT "NIVLAS BEHEMAH TEME'AH" IS "METAMEI"
QUESTION: Rebbi Yonasan asked Ben Azai if he knew the source for the Halachah that a Chayah Tehorah is Metamei when it dies. One verse states clearly that a Behemah and a Chayah Teme'ah are Metamei ("... b'Nivlas Chayah Teme'ah O b'Nivlas Behemah Teme'ah..." in Vayikra 5:2), and another verse states that a Behemah Tehorah is Metamei ("... ha'Behemah Asher Hi Lachem l'Ochlah" in Vayikra 11:39). However, there is no explicit verse in the Torah that teaches that a Chayah Tehorah is Metamei.
Ben Azai suggested a source for the Tum'ah of a Chayah Tehorah, but Rebbi Yonasan refuted it. Ben Azai then asked Rebbi Yonasan to reveal to him what source Rebbi Yonasan's Rebbi, Rebbi Yishmael, found to teach that a Chayah Tehorah is Metamei. Rebbi Yonasan replied that the correct source for the Halachah that a Chayah Tehorah is Metamei is the verse that discusses the Tum'ah of a Behemah (Vayikra 11:39, as mentioned above). The verse there begins with the words, "v'Chi Yamus Min ha'Behemah," which, Rebbi Yonasan explains, refer to a Behemah Teme'ah and teach that a Behemah Teme'ah is Metamei. The verse continues, "Asher Hi Lachem l'Ochlah." Rebbi Yonasan explains that these words refer to a Behemah Tehorah and teach that a Behemah Tehorah is Metamei. The source that a Chayah Tehorah is Metamei is based on the principle that "Chayah bi'Chlal Behemah" -- the word "Behemah" in the Torah includes Chayah as well. If the Torah says that a Behemah Tehorah is Metamei, then a Chayah Tehorah is also Metamei.
Rebbi Yonasan's answer is difficult to understand. It seem that his source for the Tum'ah of a Chayah Tehorah is simply the principle that a Chayah is included in the word "Behemah." Since the verse (11:39) teaches that a Behemah Tehorah is Metamei, then the same applies to a Chayah Tehorah. Why, then, did Rebbi Yonasan introduce a new source from the verse to teach that a Behemah Teme'ah is Metamei ("'v'Chi Yamus Min ha'Behemah' -- this refers to a Behemah Teme'ah")? The Halachah that a Behemah Teme'ah is Metamei is derived from an earlier verse ("O b'Nivlas Behemah Teme'ah" in Vayikra 5:2), as Ben Azai and Rebbi Yonasan originally understood (see RASHI DH Hachi Garsinan, and DH Tanya). (RAMBAN, CHIDUSHEI HA'RAN, MAHARSHA)
ANSWERS:
(a) The MAHARSHA answers that there is a printing error in the part of the Beraisa that quotes Rebbi Yonasan's source for the Tum'ah of a Behemah. It should not include the words, "this refers to a Behemah Teme'ah," since it is not necessary to bring a new source for the Tum'ah of a Behemah Teme'ah, as mentioned above.
To support his emendation of the text of the Beraisa, the Maharsha cites the YALKUT SHIMONI (#536) which quotes this Beraisa but leaves out the words, "this refers to a Behemah Teme'ah" (this is the text in some Girsa'os of the Yalkut).
(b) The RAMBAN and RAN suggest a way to understand the text without changing it (see also MEROMEI SADEH). They explain that the principle that a Chayah is included in the word "Behemah" alone does not suffice to teach that a Chayah Tehorah is Metamei. This is because the Torah seems to make an exception to the rule that a Chayah is included in the word "Behemah" with regard to being Metamei, because it mentions a Chayah Teme'ah explicitly (in Vayikra 5:2) even though it also mentions a Behemah Teme'ah. The Torah says that one becomes Tamei when he touches "b'Nivlas Chayah Teme'ah O b'Nivlas Behemah Teme'ah." If Chayah is included in "Behemah," then the Torah would have said only, "O b'Nivlas Behemah Teme'ah," without mentioning Chayah Teme'ah explicitly. The fact that the Torah specifies Chayah Teme'ah implies that Chayah cannot be learned from Behemah with regard to Tum'ah.
For this reason, when the Torah mentions that only a Behemah Tehorah is Metamei (in Vayikra 11:39) and does not mention explicitly that a Chayah Tehorah is Metamei, one should infer that a Chayah Tehorah is not Metamei.
This is why Rebbi Yonasan pointed out that the verse (11:39) is also teaching that a Behemah Teme'ah is Metamei, even though the earlier verse already teaches that a Behemah Teme'ah is Metamei. The apparently extra verse was written to compare the laws of a Behemah Tehorah to the laws of a Behemah Teme'ah (both of which are written in that verse) with regard to being Metamei. We find that the laws of a Behemah Teme'ah apply to a Chayah Teme'ah as well (in Vayikra 5:2) and both are Metamei. We may infer that Chayah is also included in the word "Behemah" when the verse (11:39) discusses a Behemah Tehorah. Hence, the laws of Behemah Tehorah and Chayah Tehorah are the same with regard to being Metamei; Chayah is included in the word "Behemah" in the verse that discusses the Tum'ah of a Behemah Tehorah.
If Chayah is included in "Behemah" with regard to Tum'ah, then why does the Torah specify both Behemah Teme'ah and Chayah Teme'ah in the verse in Vayikra? The answer is that this verse was written in order to teach a law about the Korban Oleh v'Yored, as Rebbi says earlier (71a; see Rashi there, DH Ekra Ani Chayah).

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