Talmud - Bava Metzia 91b בבא מציעא צ״א ב׳

Had the Torah merely stated: “You shall not let your cattle copulate,” I would have said that a person may not hold the female animal when a male mounts it. Therefore, the verse states: “With a diverse kind” (Leviticus 19:19). This shows that it is a crossbreed of diverse kinds that is prohibited, from which it may be inferred that mating an animal of one species with an animal of its own species is permitted.

Rav Aḥadvoi bar Ami infers from the baraita: And even concerning mating an animal of one species with an animal of its own species, with regard to holding, yes, this is permitted, but with regard to inserting, no, this is not allowed. The fact that the tanna specifies the act of holding indicates that inserting is prohibited even in the case of two animals of the same species. The Gemara again rejects this claim: What is the meaning of holding in this context? It means inserting. And why does the tanna call it holding? It is a euphemism.

Rav Ashi said: This matter was asked of me by the members of the house of Rav Neḥemya, the Exilarch: What is the halakha with regard to bringing into the same pen an animal of one species with two other animals, one of its own species and the other of a species different from it? Is the halakha that since there is another animal of its own species, it will be drawn after its species, and therefore there is no concern whatsoever with regard to diverse kinds, or perhaps one should not act even in this manner, in case it leads to crossbreeding? And I resolved it for them by saying that there is a prohibition, but this was not in accordance with the halakha. The reason for my decision was due to the immorality of the slaves. I reasoned that if they are permitted to engage in this practice, they will intentionally crossbreed and claim that it occurred without their intervention.

MISHNA: If a laborer was performing labor with his hands but not with his feet, or with his feet but not with his hands, e.g., pressing grapes, or even if he was performing labor only with his shoulder, this one may eat the produce of the field. Rabbi Yosei, son of Rabbi Yehuda, says: A laborer may not eat unless he performs labor with his hands and with his feet.

GEMARA: The Gemara asks: What is the reason for the ruling of the Rabbis stated in the first clause of the mishna? The Gemara explains that the verse states: “When you come into your neighbor’s vineyard” (Deuteronomy 23:25). Since the Torah does not specify a particular kind of task, it is understood as referring to any labor he performs.

The mishna teaches that Rabbi Yosei, son of Rabbi Yehuda, says: A laborer may not eat unless he performs labor with his hands and with his feet. The Gemara asks: What is the reasoning of Rabbi Yosei, son of Rabbi Yehuda? The Gemara explains: This halakha is like that of a threshing ox; just as one is not required to let an ox feed unless it is performing labor with its hands and with its feet, as it uses all four of its legs to thresh, so too a laborer is not entitled to eat unless he is performing labor with his hands and with his feet.

§ With regard to a similar issue, Rabba bar Rav Huna raised a dilemma: If one threshed with geese and chickens, rather than four-legged animals, what is the halakha according to the opinion of Rabbi Yosei, son of Rabbi Yehuda? The Gemara clarifies the sides of the dilemma: Do we require threshing with all its force, as it is for this reason that an ox must thresh with all four of its legs, and that condition is fulfilled here, as these birds perform labor with all their strength, or perhaps we require that the animal must actually perform labor with its hands and with its feet, i.e., with all four legs, and this is not the case here? No answer was found, and the Gemara says that the dilemma shall stand unresolved.

Rav Naḥman says that Rabba bar Avuh says: With regard to laborers in a vineyard, until they have walked lengthwise and crosswise in the winepress, the first stage of the making of wine, they may eat grapes, as they are performing labor with grapes, but they may not yet drink wine, since their labor has not produced wine. Once they have walked lengthwise and crosswise in the winepress, they are now performing labor with wine as well, and therefore they may eat grapes and drink wine.

MISHNA: If a laborer was performing labor with figs he may not eat grapes; if he was performing labor with grapes he may not eat figs, as he may eat only the type of food with which he is working. This is the halakha even if he was employed to perform labor with both types of produce but is currently performing labor with only one of them. But he may hold himself back from eating until he reaches a place of good-quality grapes or figs and eat from these, as they are the same type of food.

And with regard to all of these cases the Sages said that he may eat only at the time of work. But due to the obligation to restore lost property to its owners, i.e., so that workers would not neglect their task, they said that laborers may eat as they walk from one row of a vineyard or plantation to another row, and upon their return from the winepress. And with regard to a donkey, it is permitted to eat when it is being unloaded. This statement will be explained in the Gemara.

GEMARA: A dilemma was raised before the Sages with regard to the ruling of the mishna: If a laborer was performing labor on this vine, what is the halakha concerning the possibility that he may eat from another vine? Do we require only that the food must be from the type that you are placing into the homeowner’s vessels, and this condition is fulfilled here, or perhaps we require that it must be from that very food which you are placing into the homeowner’s vessels, and this is not the case here?

And if you say that one who was performing labor on this vine may not in fact eat from another vine, a further question arises: With regard to an ox performing labor with produce attached to the ground, how can one enable it to eat? The ox is tied to the front of the wagon, while the laborers are working on a vine adjacent to the wagon. Consequently, it is impossible for the ox to eat from the vine on which labor is being performed. Rav Sheisha, son of Rav Idi, said: In the case of long branches it is possible for the animal to perform labor at one end of the branch while eating from the other.

This difficulty has been resolved, but the original dilemma remains. The Gemara therefore suggests: Come and hear a resolution from the mishna: If a laborer was performing labor with figs he may not eat grapes. This indicates that if the two types of produce are figs and other figs, similar to the figs and grapes mentioned in the mishna, he may eat. Now, if you say that one who was performing labor on this vine may not eat from another vine, how can you find these circumstances? Rav Sheisha, son of Rav Idi, said: The ruling of the mishna is stated with regard to a hanging vine, and he eats from one edge of the branch while working on the other side.

The Gemara offers another suggestion: Come and hear another resolution from the mishna: But he may hold himself back from eating until he reaches a place of good-quality fruit and eat. And if you say that one who was performing labor on this vine may eat from another vine, let him go and bring and eat. Why must he wait until he reaches that particular vine? The Gemara answers: There, the reason is due to the neglect of work caused by the laborer walking to the other vine. We do not raise the dilemma with regard to that case, as he may certainly not stop performing labor to go and eat elsewhere. When the dilemma was raised before us, it was with regard to a case where his wife and children are present. What is the halakha as to whether his family members, who are not performing labor, may bring him fruit?

Once again the Gemara suggests: Come and hear a resolution from the mishna: And with regard to all of these cases they said that he may eat only at the time of work. But due to the mitzva to restore lost property to its owners, the Sages said that laborers may eat as they walk from one row to another row, and upon their return from the winepress.

The Gemara explains the attempted resolution: The Sages assumed that the basic principle of this halakha is that a laborer who was walking is considered like one who was performing his labor, and it is therefore permitted for him to eat. And yet, it is due to the mitzva to restore lost property to its owner that he may eat, whereas by Torah law he may not eat. But if he is performing labor, why is he not allowed to eat? Apparently, this indicates that one who was performing labor on this vine may not eat from another vine, and therefore once he starts walking and is no longer alongside the vine he may not partake of it by Torah law.

The Gemara refutes this argument: No; actually, I could say to you that one who was performing labor on this vine may even eat from another vine, but a laborer who was walking is not considered like one who was performing his labor. The reason that he is not permitted to eat by Torah law is not because he is performing labor on a different vine, but because he is walking at the time.

The Gemara cites an alternative version of this discussion. There are those who say as follows: The Sages assumed that a worker who was walking is not considered like one who was performing his labor, and this is the reason that the baraita says that he may not eat by Torah law: Because he is not considered like one who was performing his labor. This indicates that if he is performing his labor, he may eat by Torah law. Apparently, it may be inferred that one who was performing labor on this vine may eat from another vine.

The Gemara rejects this claim: No; this is not a proof, as actually I could say to you that one who was performing labor on this vine may not eat from another vine,

Traduction : The William Davidson digital edition of the Koren Noé Talmud, with commentary by Rabbi Adin Even-Israel Steinsaltz.

BavaMetzia 91b examines laws against crossbreeding animals of different species and the permissibility of assisting mating within the same species.