Explanation #1: Rabeinu Tam explains that this is because originally everything in the fetus is flesh. The flesh then proceeds to (have some of it) harden, whiten, and then turn into a Gid.

Explanation #2: Rashi explains later that originally when the Gid is created it is not on the "Kaf ha'Yarech" - "the quadriceps femoris muscle." The prohibition of Gid ha'Nasheh is only when the Gid comes and hardens on the Kaf.

Implied Question: The Gemara now wants to say that the prohibition against Gid ha'Nasheh does not take effect when the prohibition of Mukdashin is already present. (According to this logic, there should also be no prohibition against Aiver Min ha'Chai together with the Gid!)

Answer #1: The prohibition of Gid ha'Nasheh does fall on Aiver Min ha'Chai, as Aiver Min ha'Chai is not as stringent of a prohibition as Mukdashin.

Answer #2: Additionally, it is impossible for the prohibition against Gid to exist if it could not take effect despite the prohibition against Aiver Min ha'Chai (which is always present in every animal).

Answer #3: Additionally, the prohibition against Aiver Min ha'Chai does not take effect until it is born. This is as the Gemara says later (103a) that the case would be if it became a Treifah when most of it came out, as then the prohibition of Treifah and Aiver Min ha'Chai would take effect at the same time.

Implied Question: The Gemara could have proved the Mishnah is unlike Rebbi Yehudah by pointing out that the Mishnah says Gid ha'Nasheh applies to a fetus, and that Rebbi Yehudah argues (on that law in the Mishnah itself). (Why isn't this used as a proof that the Mishnah is unike Rebbi Yehudah?)

Answer: Rather, it proved this from an earlier statement in the Mishnah (even though the latter statement is a more explicit proof).

Explanation: This indicates that even with Shelamim after Zerikah, when it is permitted even to regular Jews, the Gemara wants to say that the prohibition of Gid does not take effect and that it is permitted to be eaten. This is despite the fact that after Zerikah the prohibition of Kodshim is no longer present.

Explanation (cont.): This is apparent from the fact that the Gemara's answer is that we can only find a case where the prohibition of Gid would apply if an animal is having a Bechor.

Question: This is difficult. Since there is currently no prohibition of Kodshim on this Shelamim, even though one could technically be liable to receive Kares for eating it for example when he is impure, why shouldn't the prohibition of Gid take effect?

Question (cont.): There is no prohibition taking effect on another prohibition, as this is comparable to the Gemara in Yevamos (32a) that says that the prohibition of a wife's sister is suspended etc. (In short, the Gemara (ibid.) explains that in a case where a person was forbidden to his brother's wife before she became his wife's sister after marrying her sister, the prohibition of her being his wife's sister is suspended until the prohibition of her being his brother's wife does not apply.)

Answer: Since the prohibition of Gid never applied when the animal was alive due to the prohibition of Mukdashin, which can possibly cause him to be liable to receive Kares due to Pigul, Nosar, or Tamei, the prohibition does not even apply after Shechitah or Zerikah. This is because we require that the prohibition of Gid be applicable when the animal is alive, comparable to Yaakov Avinu whose Gid was injured when he was alive.

Question: Why don't we say that since the prohibition of Gid was added to the sons of Noach, it should also be added to Jews (even if the animal was Mukdashin its entire life)?

Answer #1: The prohibition of Gid for Nochrim was specifically for the sons of Yaakov, who before the Torah was given were called "sons of Noach."

Answer #2: Even if one will say that all of the nations of the world were originally forbidden in Gid ha'Nasheh, the Gemara in Sanhedrin (59a) says that any Mitzvah that was said to sons of Noach and was not repeated at Har Sinai only applies to Jews and not Nochrim. Accordingly, after the Torah was given Gid ha'Nasheh is permitted to all Nochrim, but not to Jews.

Question: Why don't we say that since the prohibition of Gid is even towards Hash-m, as it is forbidden to offer it on the altar, it should also be prohibited to a regular person (even if the animal was Mukdashin its entire life)?

Answer: This opinion holds like the opinion later that says that if it is attached to the pieces that do go on the altar, it should be offered.

Explanation: The prohibitions (Gid, Mukdashin) take effect at the same time. The novelty of this Halachah is that the stringent prohibition of Kodshim does not stop the more lenient prohibition of Gid ha'Nasheh from taking effect together with it.

Question: The prohibition against Gid ha'Nasheh should take effect first according to Rebbi Yochanan (75a) who says that if one tears off Cheilev from a nine month old fetus that is alive, its fat is like the (forbidden) Cheilev of an animal. Only later does the stringent prohibition of Mukdashin take effect. If so, according to Rebbi Yochanan, the Mishnah should say that Mukdashin applies to Gid ha'Nasheh (which comes first, not that Gid applies to Mukdashin)!

Answer: It appears that according to Rebbi Yochanan the prohibition against Gid and Cheilev does not take effect until it (i.e. even the Cheilev alone) goes out of its mother's womb and into the air of the world.

Answer (cont.): This is also implied later (103a) where Rebbi Yochanan says that if the animal becomes a Treifah when most of it comes out, the prohibition of Aiver Min haChai, Cheilev, and Treifah all occur at the same time. This indicates that these (Rashash - specifically Cheilev) prohibitions do not apply in the womb.

Question: This is difficult. Why did the Gemara quote the first Beraisa (when the second Beraisa contains the argument between Rebbi and the Rabanan)?

Answer: Without the first Beraisa, it would be possible to say that the Rabanan hold that we should include whatever we can include, even if things that were forbidden became separated. We should only exclude things that fell off the altar, which are the last things that would be put back on the altar.

Answer (cont.): Rebbi holds that we should establish these inclusive and exclusive Pesukim as regarding the beginning of putting items on the altar. We should similarly exclude one thing, meaning something that was separate and forbidden. However, forbidden things connected to parts of the animal that were supposed to be put on the altar and permitted items that separated from parts that were supposed to be on the altar should be permitted to be placed on the altar.

Answer (cont.): The first Beraisa is therefore quoted to teach that the Gidim that are permitted should be taken off the altar after they were already separated, similar to bones that are permitted.

Answer (cont.): This must be according to Rebbi, indicating that Rebbi does not include anything that can be included, as he says that there is an exclusion for things that separate that are permitted. Accordingly, the Rabanan also must not include everything that can be included, but rather it must be that they exclude prohibited items even if they are attached to the meat.

Opinion #1: Rashi explains that the text should read "Chatas v'Asham" since a Shelamim is eaten in all of Yerushalayim. Otherwise, why would the Gid be discussed as being in the Azarah?

Opinion #2: It appears that (the text is correct, and Rashi's question is not difficult as) the thigh and chest of the Shelamim was given to the Kohanim. This included the Gid ha'Nasheh that was in the thigh which is the hind leg of the animal and not the foreleg, as stated by the Mishnah (134b). Kohanim were used to eating their Matanos in the Azarah (which is why it is discussed as being in the Azarah).

Opinion #2 (cont.): Another reason that the Gemara could be discussing a Shelamim is that it is referring to a Shelamim brought by Kohanim who were used to eating all of their Korbanos in the Azarah.

Explanation: However, Shmuel holds that giving the Korban Tamid a drink from a gold cup as stated in Tamid (30a) was not an exaggeration, since there is no poverty in a place of wealth.

Question #1: The Gemara in Beitzah (14b) says, why did they say that a curtain is impure? This is because the servant wraps himself in its warmth (causing it to be like clothing). There is no suspicion that one will wrap themselves in the warmth of the Paroches, as it is forbidden to benefit from it! Why, then, would it ever require immersion in a Mikvah?

Answer: One cannot say that being that it was woven they would immerse it, as stated in Chagigah (23a) that vessels that were finished with a status of purity require immersion to be used for Kodesh.

Question: The Gemara there is only referring to the immersion of vessels that can possibly become impure due to the stringency of their impending use for Kodesh. They were therefore stringent to immerse them as if they already became impure. However, a Paroches that cannot become impure should not require this immersion.

Question #2: Additionally, in Shekalim (12b) the Gemara explicitly implies that the Paroches can become impure. This is as the Mishnah states, "A Paroches that became impure from an Av ha'Tumah is immersed outside. If it became impure from a Vlad ha'Tumah, it is immersed inside."

Answer #1: It can become impure because it is a tent, as stated in Sukah (7b) "And you will hover over the Aron" implies that (a small part of it) hovers over the Aron.

Answer #2: There are some Sefarim that have the text in Beitzah (14b), "Why is a curtain forbidden?" This is also the text in the Bahag. This means, why is it forbidden to make a curtain out of Kilayim?