Gemara

(Mishnah): (On Yom Kipur, a lottery determines which of two goats is a Chatas (offered to Hash-m) and which is Mishtale'ach (sent to Azazel). If the Mishtale'ach died, we take two other goats and do another lottery. The new Mishtale'ach replaces the dead goat.) The second grazes until it gets a blemish, and the money goes to Nedavah, because Chatas Tzibur need not die.

(R. Yochanan): Living animals can become Nidchim (permanently disqualified, even if the Pesul goes away). The Chatas from the second pair is offered, and the Chatas from the first pair is like Chatas she'Avrah Shenasah.

Yoma 64a (Rav): The second animal (the Chatas) from the first pair is offered, and the second from the second pair (the Chatas) grazes;

(R. Yochanan): The second animal from the first pair grazes, and the second from the second pair is offered.

Rav holds that Ba'alei Chayim Nidchim. R. Yochanan holds that Ein Ba'alei Chayim Nidchim.

Question: What is Rav's reason?

Answer #1: He learns from Mechusar Zeman (a Korban that may not be offered yet). Even though now it is not Chazi (able to be offered), later when it becomes Chazi, we may offer it. The same applies here.

Rejection: Mechusar Zeman was never Chazi. Here, it was Chazi (before the Mishtale'ach died) and then Nidcheh!

Answer #2: He learns from a temporary Mum. Even though now it is not Chazi, later when it becomes Chazi (the Mum heals), we may offer it. The same applies here.

Question: What is the source that after a temporary Mum heals, we may offer it?

Answer: "Ki Mashchasam Bahem Mum Bam" teaches that it is not acceptable only when the Mum is in it.

R. Yochanan holds that "Bahem" teaches that only there, it is acceptable after the Mum Goes away. In other cases, once it was Nidcheh, it is (permanently) Nidcheh.

Rav expounds "Bahem" to teach that they are disqualified by themselves, but amidst a mixture, they are acceptable;

(Mishnah - R. Eliezer): If limbs of Kosher Olos became mixed with limbs of a Ba'al Mum, if one of the heads was offered, we offer all of them. If the Kerayim (bottoms of the legs) of one of them were offered, we offer all of them;

Chachamim say, even if all were offered except for one, the last one is burned in Beis ha'Sereifah.

R. Yochanan holds that the Torah could have written 'Bam' to teach this. Rather, it says "Bahem" to teach both of these.

Rav holds that this does not warrant another Drashah.

64b (Rava): The Mishnah is like Rav, and a Beraisa is like R. Yochanan.

(Mishnah): If the Chatas dies, the Chatas chosen in the second lottery is (offered) in place of it. The other (Mishtale'ach) keeps its status.

(Beraisa) Question: Does "Sheni" refer to the second of the first pair, or of the second pair?

Answer: "Ya'amod Chai" excludes when its partner died. "Ya'amod" connotes that it did not stand beforehand.

65a: Some say that the following question was asked.

(Mishnah - R. Yehudah): If the blood (of the Chatas) spilled, the Mishtale'ach must die.

Question: Granted, this is because the Mitzvah was not done yet. However, why does he say (in the Seifa) that if the Mishtale'ach died, we must spill the blood of the Chatas? Its Mitzvah was already done!

Answer: Rav's law is only according to Rabanan, but not according to R. Yehudah.

Question: Granted, Rav holds that Rav Yehudah and Rabanan argue about this. According to R. Yochanan, what do they argue about?

Answer (Rabah): Indeed, the Mishnah connotes like Rav.

Kerisus 27a (R. Yochanan): If one of two partners in an animal was Makdish his half, bought his partner's half, and was Makdish that also, the animal is Kodesh, but it cannot be offered. If one makes Temurah on it, the Temurah has the same law as it.

We learn three laws from this;

Dichuy applies to Kedushas Damim (monetary Kedushah);

A living animal can be Nidcheh;

Dichuy me'Ikara (it was Pasul from the start) is considered Dichuy.

Pesachim 98a (Mishnah): If one was Makdish a female for Korban Pesach, it is Ro'eh. He buys Shelamim with the money.

(Rav Huna brei d'Rav Yehoshua): We learn three laws from this:

A living animal can be Nidcheh (if not, the female itself would be offered for a Shelamim);

Dichuy me'Ikara is considered Dichuy;

Dichuy applies to Kedushas Damim.

Zevachim 59a (Rav): If Korbanos were slaughtered and then the Mizbe'ach became dented, they are (permanently) Pesulim;

(R. Shimon bar Rebbi citing R. Yishmael b'Rebbi Yosi): We learn from "v'Zovachta Alav Es Olosecha v'Es Shelamecha."

(R. Yochanan): Even if a Korban was slaughtered after the Mizbe'ach was fixed, it is Pasul (if it was Kodesh when the Mizbe'ach was broken).

They argue about whether Ba'alei Chayim are Nidchim.

73a (Rava): Since Chachamim forbade offering Korbanos that became mixed, if any were offered, they are Pesulim.

Question (Rav Huna bar Yehudah - Mishnah): If Chata'os and Olos became mixed, and a Kohen erred and offered all of them above, half are Kesherim (the Olos).

Answer: Rava's law is like the opinion that Ein Ba'alei Chayim Nidchim. The Mishnah holds that Ba'alei Chayim Nidchim.

Rishonim

Rambam (Hilchos Ma'aseh ha'Korbanos 15:4): If one of two partners in an animal was Makdish his half, bought his partner's half, and was Makdish that also, the animal is Kodesh, and it can be offered. Even though it was initially Nidcheh when only half was Kodesh, Dichuy me'Ikara is not considered Dichuy. Even though it was Kodshei Kodoshim, since it is Ba'alei Chayim, Ein Ba'alei Chayim Nidchim.

Kesef Mishneh: We say in Pesachim that the Mishnah (98a) is like R. Yochanan. The Rambam rules unlike R. Yochanan because the Gemara in Yoma says that the Mishnah supports Rav. Also, since that Mishnah supports Rav, and the Mishnah in Pesachim supports R. Yochanan, we can say that the latter is like R. Yehudah, i.e. an individual's opinion. Also, R. Shimon bar Rebbi and R. Yishmael b'Rebbi Yosi hold like Rav (Zevachim 59a). Also in Zevachim 73a we say that the Stam Mishnah in Kinim holds that Ein Ba'alei Chayim Nidchim.

Tosfos (Yoma 64b DH Beraisa): Why did we support R. Yochanan from a Beraisa? We should support him from the Mishnah in Pesachim. The Gemara derived from it that Ein Ba'alei Chayim Nidchim! I answer that there it is full Dichuy, for a female can never be a Pesach. This also explains the Chidush of R. Yochanan (if a partner was Makdish his half, the animal can never be offered). We cannot learn this from the Mishnah of Pesachim, for there it is full Dichuy.

Lechem Mishneh: The Kesef Mishneh gave proper reasons for the Rambam, except for saying that the Mishnah in Pesachim is an individual's opinion. The Rambam (Hilchos Korban Pesach 4:4) rules like that Mishnah! Rather, he distinguishes like Tosfos. Full Dichuy applies even to Ba'alei Chayim.

Tosfos (Zevachim 59a DH Ad): The Gemara connotes that the first question (it was Dichuy me'Ikara) applies even to R. Yochanan, i.e. so he must agree that the Beraisa must be corrected. This is difficult, for he holds that Dichuy me'Ikara is Dichuy! The Mishnah in Pesachim teaches this! I answer that there, he cannot fix it, therefore it is Dichuy. Here, he can fix the Mizbe'ach. The Gemara holds that all agree that there is no Dichuy in such a case, just like Mechusar Zeman of the animal or the owner, e.g. a Yoledes or Metzora who was Makdish a Korban before he or she may offer it. This is why a Korban Hukdash when the Mishkan was in Gilgal was permitted to be offered (after the Mishkan was erected) in Shilo (Zevachim 114a).

Kesef Mishneh (citing the Me'iri, Kidushin 7a): Why did the Rambam say 'even though it is Kedushas Damim'? When there is only Kedushas Damim, it is more proper to say that it is not Nidcheh!

Lechem Mishneh: The Rambam connotes that Dichuy me'Ikara did not suffice by itself for Kedushas Damim. He added 'since it is Ba'alei Chayim.' In Hilchos Shegagos (10:13), he wrote only 'because it is Dichuy me'Ikara.' He relied on what he wrote here. However, why does he require a second reason? Tosfos asked from places in which we find that Dichuy me'Ikara is Dichuy, and answered that when he can fix it, it is not Dichuy. The Rambam explains opposite to Tosfos and Rashi. "Yesh Dichuy b'Damim" means that surely Ein Dichuy regarding Kedushas ha'Guf, but Yesh Dichuy regarding Kedushas Damim. The Rambam rules like Ein Ba'alei Chayim Nidchim, like the Kesef Mishneh explained, and Dichuy me'Ikara is not Dichuy, due to the Gemara's question (59a). Regarding Kedushas Damim, we say Ein Dichuy only if it is Ba'alei Chayim. Tosfos asked that every case of Dichuy me'Ikara is Kedushas Damim, so R. Yochanan taught only two laws! The Rambam holds that there is no Dichuy regarding Kedushas ha'Guf! Rather, R. Yochanan teaches two Chidushim in one law. 1) Dichuy me'Ikara is Dichuy. 2) Dichuy applies to Kedushas Damim. The latter law could apply also to Mitzvos, like the Gemara (Sukos 32b) asked. R. Yochanan teaches that it does not apply to Mitzvos, only to Kedushas Damim.

Rebuttal #1 (Tzlach Sukah 32b DH veha'Davar): R. Yochanan learns from a verse that Ba'alei Chayim Nidchim. He was unsure about Dichuy regarding other Mitzvos. If so, since Rav holds that Ein Ba'alei Chayim Nidchim, surely Ein Dichuy regarding Mitzvos. The Sugya (about whether Yesh Dichuy regarding Mitzvos) was only according to R. Yochanan. The Rambam rules like Rav, therefore he holds that Ein Dichuy regarding Mitzvos.

Rebuttal #2 ((Keren Orah Zevachim 12b DH v'Adayin): Zevachim 12a refutes the Lechem Mishneh. If one was Makdish a Korban Pesach before midday (of Erev Pesach, before one may offer it), it has Kedushas ha'Guf, and R. Yochanan holds that Dichuy applies. Rather, the Rambam says Ein Dichuy me'Ikara to teach about things other than Ba'alei Chayim. The Rambam holds that our Sugya (which says Yesh Dichuy me'Ikara) argues with 59a, in which we say that Ein Dichuy me'Ikara. He does not distinguish like Tosfos, and he does not distinguish Mitzvos from Kodshim; they are the same.

Poskim

Gra (YD 110:10): Why does the Rambam rule like Rav, who holds like R. Eliezer (regarding offering a mixture of limbs of a Ba'al Mum)? The Rambam himself rules like Chachamim! The other Poskim hold that Rav's law is even like Chachamim. There is different, for Ba'alei Chayim Nidchim, and all the more so slaughtered animals are Nidchim. We hold like R. Yochanan, that Ba'alei Chayim Nidchim. However, the Rambam rules like Rav. This is difficult, for the Sugya is like R. Yochanan in many places. I answer that Rav's law is only when it fell (became mixed) by itself.