1) THE POINT AT WHICH AN ANIMAL IS CONSIDERED DEAD
OPINIONS: The Gemara quotes the Mishnah in Ohalos (1:6) which states that when the head of animal is severed, the animal is considered to be dead and is Tamei, even if it is still moving. Its movement is no sign of life, just as the movements of the tail of a lizard after it has been cut off from the lizard is no sign of life. The Gemara asks what the Mishnah means when it says that the head was "severed." Reish Lakish explains that it means that the head has been completely severed from the body. Rebbi Asi in the name of Rebbi Mani explains that it is like the separation of the head of the Olas ha'Of, meaning that the Simanim and neckbone (Mafrekes) have been cut, but the head has not been totally severed from the body.
The Gemara earlier (20b) quotes Ze'iri who says that when the neckbone of an animal is cut together with the flesh above it, the animal is considered a Neveilah (and is Metamei), even if the Simanim are then cut properly. Since the animal has already been rendered a Neveilah, cutting the Simanim accomplishes nothing. Ze'iri seems to be inconsistent with the Mishnah in Ohalos, especially according to the interpretation of Reish Lakish, who understands that the Mishnah requires the head to be severed before the animal is considered dead. Does Ze'iri indeed argue with the Mishnah in Ohalos?
(a) RASHI (DH Hutezu) writes that the Mishnah in Ohalos is discussing the eight Sheratzim that are Metamei, and not birds and animals. The RASHBA explains that Rashi understands that since the Gemara does not question Ze'iri from the Mishnah there, it is evident that Ze'iri is not arguing with the Mishnah.
How, though, does the fact that the Mishnah is discussing Sheratzim mean that the Mishnah does not contradict the ruling of Ze'iri? Why should Sheratzim be any different from birds and animals?
1. The LEV ARYEH suggests that since the Chachamim are very stringent with regard to the amount of a Sheretz that is considered Tamei (the size of a lentil), they are lenient with regard to its time of death and consider a Sheretz to be dead only when its death is certain. With regard to an animal or bird which requires a much larger quantity to cause Tum'ah, the Chachamim are more stringent with regard to its death and consider is death to occur even before the head is severed.
2. Alternatively, the Lev Aryeh explains that the neckbone of a Sheretz is extremely thin and flexible, and it is not the main source of the Sheretz's life, unlike an animal. The ruling of whether or not a Sheretz is dead and Tamei is therefore not contingent on the status of its neckbone, unlike an animal.
The Lev Aryeh adds that this seems to be the opinion of the RAMBAM, who records this Halachah only with regard to Sheratzim (Hilchos Avos ha'Tum'ah 4:14) but not with regard to birds and animals. In addition, the Rambam records the Halachah of Ze'iri with regard to birds and animals (Hilchos She'ar Avos ha'Tum'os 2:1).
(b) TOSFOS (DH Hutezu Rosheihen, and DH Hutezu Mamash) says that the Mishnah in Ohalos is discussing birds and animals. Tosfos says that it appears that "they" argue with Ze'iri's ruling that the cutting of the neckbone and the flesh on it is enough to make an animal a Tereifah.
The ROSH YOSEF says that the clear implication of the word "they" in Tosfos is that according to both Reish Lakish and Rebbi Asi, the Mishnah in Ohalos argues with Ze'iri. It is clear that Reish Lakish understands that the Mishnah in Ohalos argues with Ze'iri, since he says that the entire head must be completely severed in order for the animal to be considered dead. Tosfos understands that even Rebbi Asi maintains that the Mishnah argues with Ze'iri, since Rebbi Asi says that the Mishnah means that the head has been cut in the same process that is done to the Olas ha'Of, which includes (l'Chatchilah) most of the flesh on top of the neckbone.
However, the RASHBA says that even if the Mishnah is discussing birds and animals, and Reish Lakish and Rebbi Asi understand that the Mishnah contradicts Ze'iri, there is no contradiction from the Mishnah itself to the words of Ze'iri. Ze'iri may have understood that the "cutting off" of the head described in the Mishnah in Ohalos actually means that the neckbone and most of the flesh on top of it have been cut, but no more, consistent with his own ruling.
The YAM SHEL SHLOMO also explains that the Mishnah in Ohalos is discussing animals and not Sheratzim, but the Mishnah according to Rebbi Asi's interpretation is not arguing with the Halachah of Ze'iri. He explains that Rebbi Asi understands that the Mishnah means that the animal is considered dead when the Simanim and the neckbone are cut (before Rov Basar, most of the flesh around the neckbone, is cut), while Ze'iri is referring to when the neckbone and flesh on top of the neckbone are cut (before the Simanim are cut). The Mishnah is discussing cutting the head of the animal from a different angle than the cut that Ze'iri is discussing, and they are not arguing. (Y. MONTROSE)

21b----------------------------------------21b

2) LEARNING FROM "CHATAS BEHEMAH" THAT AN "OLAS HA'OF" MUST BE BROUGHT FROM "CHULIN"
QUESTION: The Torah states, "v'Es ha'Sheni Ya'aseh Olah ka'Mishpat" -- "and the second [bird] he shall make an Olah according to its law" (Vayikra 5:10). The Gemara (21a) says that the word "ka'Mishpat" refers to the laws of Chatas Behemah. The Torah clearly teaches that many laws of a Olas ha'Of are to be derived from the laws of a Chatas Behemah. The Gemara mentions that one of these laws is the requirement to bring the Korban from Chulin. Just as a Chatas Behemah must be brought only from Chulin, an Olas ha'Of must be brought only from Chulin.
Why does the Gemara need to learn this Halachah from Chatas Behemah? The Gemara in Chagigah (8a) quotes a Beraisa that states a general rule that any Korban that one is obligated to bring must be brought from Chulin. Why does the Gemara here need a special teaching of "ka'Mishpat" in order to derive the law that an Olas ha'Of must be brought from Chulin?
ANSWERS:
(a) The RASHBA, RAN, and RAMBAN answer that the Gemara in Chagigah derives its rule (that any Korban that one is obligated to bring must be brought from Chulin) from the verse, "Misas Nidvas Yadcha" -- "with the tribute of voluntary freewill offerings that you give" (Devarim 16:10). This verse, they explain, is stated specifically with regard to the Olas Re'iyah (the Korban Olah that one must bring upon visiting the Beis ha'Mikdash during each of the Shalosh Regalim). RASHI in Chagigah (DH Misas) explains that the word "Misas" teaches that the Olas Re'iyah must be brought from Chulin. Accordingly, that verse teaches only that Korbanos like the Olas Re'iyah -- Korbanos that everyone is obligated to bring three times a year -- must be brought from Chulin. A Korban such as an Olas ha'Of which is brought because of a sin (although it is not always brought because of a sin) is not comparable to an Olas Re'iyah, and thus one might be able to bring it from Ma'aser. Unlike Olas Re'iyah, which is an automatic obligation three times a year, the person did not have to be obligated to bring the Korban Olas ha'Of; he brought this obligation upon himself by sinning. The Gemara here, therefore, needs a different source to teach that this Korban also must be brought from Chulin.
RAV YOSEF SHALOM ELYASHIV shlit'a (quoted in HE'OROS L'MASECHES CHULIN) asks that according to these Rishonim, the teaching in Chagigah seems redundant. What is the source that a Chatas Behemah must be brought from Chulin? The Gemara later (22a) learns that it is derived from the Par ha'Chatas that Aharon brought on Yom Kippur. The verse says "Asher Lo" -- "that is to him" (Vayikra 16:6), which, the Gemara understands, means that it must belong to him and cannot come from Ma'aser. This certainly implies that a Korban which is a set obligation cannot come from Ma'aser, but must come from Chulin. Why, then, does the Gemara need both the verse of Olas Re'iyah (Devarim 16:10) and the verse in which Olas ha'Of is derived from Chatas Behemah (Vayikra 5:10) to teach that an obligatory Korban may not be brought from Ma'aser?
Based on Rav Elyashiv's comments, it seems that there is an even more pressing question. According to these Rishonim, who say that the law that an Olas ha'Of must be brought from Chulin cannot be derived from the Gemara in Chagigah (8a) (because the Gemara there refers only to a set obligation), how can the Gemara derive from the Par of Aharon on Yom Kippur that a Chatas Behemah must be brought from Chulin? The Par of Aharon is also a set obligation!
Rav Elyashiv's answer resolves both questions. He explains that since the verse of the Par of Aharon is extra (because, as the Gemara in Chagigah teaches, a similar verse already teaches this law), it must be that the verse of the Par of Aharon teaches that any Chatas must be brought from Chulin, even if it is not a set obligation. This is the Gemara's source that this law applies to a Chatas Behemah, and hence to an Olas ha'Of.
(b) TOSFOS in Chagigah (8a, DH Melamed) apparently disagrees with the answer of these Rishonim. Tosfos understands that the primary verse that teaches that Korbanos must be brought from Chulin is the verse of the Par of Aharon, and that the verse cited in Chagigah refers to Shalmei Chagigah and not to the Olas Re'iyah. A separate verse is needed for the Shalmei Chagigah because of a special rule that exists with regard to that Korban: one may bring a portion of his Shalmei Chagigah from Ma'aser (see Chagigah 8a). One might have thought that since a portion of the Chagigah may be brought from Ma'aser, the Torah permits the Shalmei Chagigah to be brought entirely from Ma'aser. Therefore, a special verse is needed to teach that Shalmei Chagigah may not be brought entirely from Ma'aser. This implies that the law for every other obligatory Korban is learned from the Par of Aharon, regardless of whether the Korban has a set obligation. (Y. MONTROSE)
3) DERIVING TWO LAWS FROM ONE VERSE
QUESTION: The Beraisa teaches that according to the Tana Kama and Rebbi Yishmael, two verses teach the requirement to perform "Havdalah" (separating the head of the bird from its body) as part of the Melikah of an Olas ha'Of: "v'Hikrivo" (Vayikra 1:15) and "u'Malak [Es Rosho] v'Hiktir" (ibid.). The Gemara (22a) explains that the verse "u'Malak... v'Hiktir" alone is not enough to teach that Havdalah must be performed, because that verse may be understood to be teaching a different Halachah entirely. Therefore, the other verse, "v'Hikrivo," is necessary. The Gemara, however, does not ask why the verse of "u'Malak" is necessary if the requirement of Havdalah can be derived from the verse of "v'Hikrivo." Why is the verse of "u'Malak" necessary?
One might have suggested that "v'Hikrivo" teaches only to cut a majority of the two Simanim while doing Havdalah, and "u'Malak" teaches to cut the entire diameter of the Simanim. However, RASHI (DH Talmud Lomar) writes that "v'Hikrivo" alone implies that the entire diameter of the two Simanim must be cut (since the verse does not specifically state otherwise). Why, then, do the Tana Kama and Rebbi Yishmael need the verse of "u'Malak v'Hiktir"?
ANSWER: The MAHARSHA explains that the Tana Kama indeed needs a verse to prove that the entire diameter of the Simanim is cut. According to his reading of the verse, "ka'Mishpat" (Vayikra 5:10), the Torah is comparing the Olas ha'Of to the Chatas Behemah (see previous Insight). Since the Chatas Behemah needs nothing more than the Shechitah of a majority of its Simanim, another verse is necessary to teach that all of the Simanim of the Olas ha'Of must be cut. Rashi means that Rebbi Yishmael does not need another verse to teach that the entire diameter of the Simanim must be cut.
Rebbi Yishmael, on the other hand, has no reason to assume that Havdalah of most of the Simanim suffices. Why, then, does he also learn Havdalah from "u'Malak v'Hiktir," when the verse of "v'Hikrivo" should suffice?
The RASHBA explains that Rebbi Yishmael is unsure about whether to compare Olas ha'Of to Chatas ha'Of (through the verse, "ka'Mishpat") with regard to cutting from the "Mul Oref" (the back of the neck) and to differentiate between them (through the verse, "v'Hikrivo") with regard to Havdalah, or the opposite -- to compare them with regard to Havdalah and to differentiate between them with regard to cutting from the "Mul Oref." Therefore, Rebbi Yishmael needs the verse of "u'Malak" to reveal that the two are differentiated with regard to the requirement of Havdalah. (This is also the intention of Rashi, beginning of DH Talmud Lomar.)
Rebbi Elazar b'Rebbi Shimon, in contrast, does not learn the laws of Melikah from "u'Malak v'Hiktir" at all. According to his opinion, the verse "v'Hikrivo" alone suffices to teach the requirement of Havdalah for an Olas ha'Of.

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