With regard to one who slaughters from within the rest of the rings, even though they do not encircle the entire windpipe, since they encircle the majority of the windpipe his slaughter is valid. The baraita adds: And in a case where the knife is diverted from the place of slaughter above the ring, the slaughter is not valid. Rabbi Ḥanina ben Antigonus testified about a case where the knife is diverted from the area of slaughter above the ring that in such a case the slaughter is valid. Contrary to that which Rav and Shmuel said with regard to the opinion of Rabbi Yosei, son of Rabbi Yehuda, he holds that slaughter from within the other rings is valid.

Rav Yosef said: Rabbi Yosei bar Yehuda is saying two statements; Rav and Shmuel hold in accordance with his opinion with regard to one matter, that if one cuts a majority of the windpipe within the large ring the slaughter is valid, and disagree with him with regard to one matter, as in their opinion if one cuts the windpipe within the other rings, the slaughter is not valid.

The Gemara objects: But didn’t Rav and Shmuel say: And even Rabbi Yosei, son of Rabbi Yehuda, said his statement only with regard to the large upper ring and not with regard to the other rings, indicating that in their opinion, this is the opinion of Rabbi Yosei, son of Rabbi Yehuda? The Gemara explains that this is what Rav and Shmuel are saying: The halakha is in accordance with the opinion of Rabbi Yosei, son of Rabbi Yehuda, with regard to cutting the majority of the windpipe within the large ring, and the halakha is not in accordance with his opinion with regard to the other rings that since they encircle a majority of the windpipe, one may slaughter within them as well.

When Rabbi Zeira ascended from Babylonia to Eretz Yisrael, he ate meat from an animal during whose slaughter the knife was diverted from the place of slaughter, with regard to which Rav and Shmuel ruled that the slaughter is not valid, and in Eretz Yisrael the ruling was that the slaughter is valid. The Torah scholars in Eretz Yisrael said to Rabbi Zeira: Aren’t you from Babylonia, the place where Rav and Shmuel are the halakhic authorities? You should follow their ruling. Rabbi Zeira said to them: Who said this halakha citing Rav and Shmuel? It was Yosef bar Ḥiyya, referring to Rav Yosef. Yosef bar Ḥiyya learns from everyone, even from students of Rav and Shmuel who misquote their statements.

Rav Yosef heard the comment of Rabbi Zeira and was angry. He said: Do I learn from everyone? I learn from Rav Yehuda, who is so meticulous in citing the statements of Rav and Shmuel that he cites even uncertainties with regard to attribution of statements to the men who said them. As Rav Yehuda says that Rabbi Yirmeya bar Abba says, and it is uncertain whether it is in the name of Rav and uncertain whether it is in the name of Shmuel: A tribunal of three permits slaughter of a blemished firstborn animal outside of the Temple in a place where there is no expert Sage to consult.

The Gemara asks: And does Rabbi Zeira not accept the principle that when a person travels from place to place, the Sages impose upon him the stringencies of the place from which he emerged and the stringencies of the place to which he went?

Abaye said: That statement applies when one travels from one place in Babylonia to another place in Babylonia, or from one place in Eretz Yisrael to another place in Eretz Yisrael, or alternatively, when one descends from Eretz Yisrael to Babylonia. But when one ascends from Babylonia to Eretz Yisrael, this principle does not apply. Since we, the residents of Babylonia, are subordinate to them in terms of halakha, we act in accordance with their custom.

Rav Ashi said: Even if you say that when one travels from Babylonia to Eretz Yisrael, he is required to act stringently in accordance with the custom of the place from which he emerged, that statement applies only in a case where his intent is to return. Rabbi Zeira was not one whose intent was to return. Therefore, he was not obligated to observe the Babylonian stringencies.

Abaye said to Rav Yosef: But didn’t the Sages who came from Meḥoza say that Rabbi Zeira says in the name of Rav Naḥman: In a case where the knife is diverted from the place of slaughter above the ring, the slaughter is valid? Rav Yosef said to him: Each river and its unique course, i.e., each place follows its custom, and in Meḥoza the custom was not in accordance with the opinion of Rav and Shmuel.

The Gemara relates that Rabbi Shimon ben Lakish deemed the slaughter valid in a case where one cut the windpipe at the tip of the thyroid cartilage that is above the large ring. Rabbi Yoḥanan proclaimed about Rabbi Shimon ben Lakish: He greatly exaggerated the limits of valid slaughter. Rav Pappi said in the name of Rava: If one cut the windpipe and encountered the arytenoid cartilage that is adjacent to the upper ring in the direction of the jaw and covered by the tip of the thyroid cartilage, the animal is a tereifa, i.e., forbidden. Since the arytenoid cartilage is outside the area of slaughter, the slaughter is invalid.

A dilemma was raised before the Sages: Does encountered mean encountered and touched it, as it is written: “And he encountered him and he died” (I Kings 2:25); or perhaps it means encountered but did not touch, like that which is written: “And the angels of God encountered him” (Genesis 32:2)?

It was stated that Rav Pappa said in the name of Rava: If one left part of the arytenoid cartilage, i.e., if he cut it in the middle, the slaughter is valid. Rav Ameimar bar Mar Yenuka said: I was standing before Rabbi Ḥiyya, son of Rav Avya, and he said to me: If one left part of the arytenoid cartilage, the slaughter is valid. Ravina said to Rav Ashi: Rav Shemen of Suvara said to me that Mar Zutra happened to come to our place and taught: If one left part of the arytenoid cartilage, the slaughter is valid. Mar bar Rav Ashi said: If one encountered the arytenoid cartilage, the slaughter is valid. If one left part of the arytenoid cartilage, the animal is a tereifa.