Talmud - Nedarim 38b נדרים ל״ח ב׳

both its being and its body belong to Heaven, as it is prohibited for its owner to eat its meat. The Rabbis said to him: The non-kosher animal too, its being belongs to Heaven, and its body is the property of its owner, because if the owner chooses, he sells it to gentiles or feeds it to dogs.

GEMARA: Rav Yitzḥak bar Ḥananya said that Rav Huna said: In the case of one for whom benefit from another is forbidden by vow, he is permitted to marry his daughter to him. Rabbi Zeira discussed it: With what case are we dealing? If we say that it is a case where the property of the father of the bride is forbidden to the groom, this cannot be, as when one marries his daughter to the groom, he provides him a maidservant to serve him and thereby benefits him.

Rather, it is a case where the property of the groom is forbidden to the father of the bride, and although the groom supports the bride, her father is not considered to have benefited from the property of the groom. However, it cannot be this case either, as the Sages stated a halakha with a greater novel element than that in the mishna itself: And with regard to one for whom benefit from another is forbidden by vow, that other person may feed his wife and children, although the one who is bound by the vow is obligated in their support. And you say that it is permitted to marry his daughter to him? Isn’t that obvious?

The Gemara answers: Actually, it is a case where the property of the father of the bride is forbidden to the groom, and where his daughter is a grown woman, and where her father may marry her to another only with her consent. Therefore, it is not from her father that the groom is deriving benefit.

The Gemara comments: That is also taught in a baraita. In the case of one for whom benefit from another is forbidden by vow, it is prohibited for that other person to marry his daughter to him. However, he may marry off his daughter, who is a grown woman, to that other person with her consent.

Similarly, Rabbi Ya’akov said: If one vows that benefit from him is forbidden to his son, in order to induce him to engage in Torah study, the one who took the vow may nevertheless perform actions that provide his son with minor benefit. It is permitted for him to fill a barrel of water for his son and to kindle a lamp for him. Rabbi Yitzḥak said: It is permitted for him to roast a small fish for him. Rabbi Yirmeya said that Rabbi Yoḥanan said: In the case of one for whom benefit from another is forbidden by vow it is permitted for the other to give him a cup of peace to drink. The Gemara asks: What is this cup of peace? Here, in Babylonia, the Sages interpreted this term as referring to a cup of wine given to mourners to drink at the meal of comfort in the house of mourning. In the West, Eretz Yisrael, the Sages said that it is the cup of wine that one drinks upon leaving the bathhouse.

§ We learned in the mishna: And he may not feed the animal of one for whom benefit from him is forbidden, whether it is a kosher animal or whether it is a non-kosher animal. It is taught in a baraita that Yehoshua of Uzza says: One who vows that benefit from him is forbidden to another may feed the other person’s Canaanite slaves and maidservants; however, he may not feed his animal, whether it is a non-kosher animal or whether it is a kosher animal. The Gemara asks: What is the reason for the distinction? The Gemara explains: His Canaanite slaves and maidservants are designated for labor, whereas an animal is designated for fattening. The one bound by the vow derives benefit from the other person feeding the kosher animal when he eats it and derives benefit from the other person feeding the non-kosher animal when he sells it to a gentile.

MISHNA: In the case of one for whom benefit from another is forbidden by vow and he enters his house to visit him, he stands there but does not sit. And that other person heals him with a cure of the nefesh but not a cure of mamon.

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

Nedarim 38b explores vow-based restrictions on deriving benefit, examining rules for marrying off a daughter and supporting a spouse's family under such vows.