if the measure of the skin is enough to impart flavor to the milk, that cheese is prohibited. In the case of a kosher animal that suckled milk from a tereifa, the milk in its stomach is prohibited, as the milk is from the tereifa. If it was a tereifa that suckled milk from a kosher animal, the milk in its stomach is permitted, as the milk is from the kosher animal. In both cases, the milk that an animal suckles has the status of the animal from which it was suckled, and not that of the animal which suckled, because the milk is collected in its innards and is not an integral part of its body.

GEMARA: The mishna makes reference to the stomach of the animal of a gentile and that of an unslaughtered carcass. The Gemara asks: Is that to say that the stomach of an animal slaughtered by a gentile is not itself a carcass? Why does the tanna of the mishna differentiate between them? Rav Huna said: The mishna here is not referring to an animal slaughtered by a gentile. Rather, we are dealing with a Jew who purchases a kid from a gentile and slaughters it himself. Therefore, the kid is not prohibited as a carcass, but we are concerned that perhaps it suckled from a tereifa animal, and it is therefore prohibited.

The Gemara asks: And are we concerned that perhaps it suckled from an animal that is a tereifa? But didn’t we learn in a baraita (Tosefta 3:8): One may purchase eggs from gentiles, and we are not concerned that perhaps the eggs came from a carcass nor that they came from a tereifa. The Gemara answers: Indeed, there is no concern that the kid might have suckled from a tereifa. Rather, say that we are concerned that perhaps it suckled from a non-kosher animal, and therefore the milk in its stomach is prohibited.

The Gemara asks: And what is different about a tereifa that we are not concerned that perhaps the animal suckled from it, and what is different about a non-kosher animal that we are concerned? The Gemara answers: A tereifa animal is not common, whereas a non-kosher animal is common, and it is therefore more likely that the young animal suckled from one.

The Gemara raises a difficulty: If suckling from a non-kosher animal is common, then let us be concerned even with regard to our own animals. The Gemara responds: We Jews, who separate ourselves from non-kosher animals, when we see them we immediately distance our suckling animals from them. Therefore, the Sages did not issue a decree with regard to animals purchased from Jews. But as for the gentiles, who do not separate themselves from non-kosher animals, when they see them they do not distance their kosher animals from them. Consequently, the Sages issued a decree with regard to animals purchased from a gentile.

And Shmuel said a different explanation of the mishna’s language: The tanna of the mishna is teaching only one halakha: The congealed milk in the stomach of an animal slaughtered by a gentile is like a carcass, and it is therefore prohibited.

The Gemara asks: And did Shmuel actually say this? Does he hold that the milk in the stomach of an unslaughtered animal is prohibited as if it were part of its body? But didn’t Shmuel say: For what reason did the Sages prohibit the cheese of gentiles? It is because they curdle it with the skin of the stomach of a carcass. One may infer consequently that congealed milk, or rennet, from the stomach of a gentile’s animal is itself permitted and would not render the cheese prohibited if used as a coagulant.

The Gemara answers: That is not difficult. Elsewhere (Avoda Zara 29b), Rabbi Yehoshua teaches two reasons for the prohibition on gentile cheese. Initially, he held it to be prohibited because it is curdled using rennet from the stomach of an animal carcass. He later adopted the opinion that such rennet is permitted, and that the cheese is prohibited because it is curdled using rennet from the stomach of calves used for idol worship, which is prohibited. Therefore, the mishna here, which states that the rennet in a carcass’s stomach is itself prohibited, was taught before Rabbi Yehoshua’s retraction, while Shmuel’s statement there, that the Sages prohibited gentile cheese only because it is curdled with the skin of the stomach of a carcass, was after Rabbi Yehoshua’s retraction.

§ The mishna teaches: In the case of a kosher animal that suckled milk from a tereifa, the milk in its stomach is prohibited, whereas if a tereifa suckled milk from a kosher animal, the milk in its stomach is permitted. The Gemara raises a difficulty: But doesn’t the first clause of the mishna teach: The congealed milk in the stomach of the animal of a gentile and of a carcass is prohibited? What is the difference between the milk found in the stomach of a tereifa in the second clause and the milk found in the stomach of an unslaughtered carcass in the first clause?

Rav Ḥisda said: In fact, milk found in the stomach of a carcass is not itself prohibited. The first clause of the mishna prohibits it only because one who partakes of it looks like one who eats carcasses, which is repulsive. By contrast, here, with regard to a tereifa, the consumption of milk found in its stomach is less repulsive, as here there is at least slaughter of the animal.

Rava said to Rav Ḥisda: But is it not possible to claim a fortiori that milk found in the stomach of a tereifa should be prohibited? Just as with regard to a carcass, which is so repulsive that even if you permit the milk in its stomach people will not come to partake of the meat, you nevertheless said the milk is not permitted for consumption, is it not all the more so with regard to a tereifa that has been slaughtered, which is not as repulsive, such that if you permit the milk in its stomach people might come to partake of it?

Rather, Rav Yitzḥak said that Rabbi Yoḥanan says: This question is not difficult. The first clause of the mishna here, which teaches that the milk in the stomach of a carcass is prohibited, was taught before Rabbi Yehoshua’s retraction cited above, whereas the latter clause there, that milk from the stomach of a tereifa is permitted, was taught after Rabbi Yehoshua’s retraction. A mishna can sometimes preserve an older ruling and then immediately teach a contradictory later ruling, because a mishna does not move from its place. Since the first clause of the mishna was already canonized, it was not removed, despite Rabbi Yehoshua’s change of opinion.

§ Rabbi Ḥiyya bar Abba says that Rabbi Yoḥanan says: One may curdle milk with rennet extracted from the stomach of carcasses, but one may not curdle milk with rennet from the stomach of animals slaughtered by a gentile. Rabbi Shimon bar Abba said before Rabbi Ḥiyya bar Abba: In accordance with whose opinion is this ruling? It is in accordance with the opinion of Rabbi Eliezer, who said: A gentile’s presumed intention during slaughter is for idol worship. Therefore, the prohibition against deriving benefit from an animal slaughtered in idol worship applies to it, and this prohibition includes the contents of its stomach that are not actually part of its body. By contrast, a carcass is prohibited only for consumption, and the prohibition does not extend to the contents of its stomach.

Rabbi Ḥiyya bar Abba said to Rabbi Shimon bar Abba: Rather, in accordance with whose opinion could this ruling be? Of course it is the opinion of Rabbi Eliezer.

The Gemara relates: When Rav Shmuel bar Rav Yitzḥak came from Eretz Yisrael to Babylonia, he said that Rabbi Yoḥanan said: One may curdle milk both with rennet from the stomach of a carcass and with rennet from the stomach of an animal slaughtered by a gentile, as there is no need to be concerned for the statement of Rabbi Eliezer. According to this account, Rabbi Yoḥanan does not maintain that a gentile’s presumed intention is for idol worship.

The Gemara concludes: And the halakha is: One may not curdle milk with the skin of the stomach of a carcass, but one may curdle milk with rennet from the stomach of a carcass and with rennet from the stomach of an animal slaughtered by a gentile, and with rennet from the stomach of a kosher animal that suckled from a tereifa, and all the more so with rennet from the stomach of a tereifa animal that suckled from a kosher animal. What is the reason for these lenient rulings? The milk collected in a stomach is merely secretion and is not considered food that can be prohibited.

MISHNA: Although animal fats and blood are similar in that they are both prohibited by Torah law and punishable by karet, there are elements more stringent in the prohibition of fat than in that of blood, and likewise there are elements more stringent in the prohibition of blood than in that of fat. The elements more stringent in the prohibition of fat are the following: The first is that with regard to fat of an offering,