Nedarim 9:4-5

Nedarim 9:4

Rabbi Meir also said that an opening to annul a vow can be made from what is written in the Torah. They say to him, “If you had been aware that you were violating the prohibitions against taking vengeance and bearing a grudge (Leviticus 19:18), as well as hating your brother in your heart (Lev. 19:17) and loving your neighbor as yourself (Lev. 19:18) and that your brother may live with you (Lev. 25:36) because if he becomes impoverished you will not be permitted to support him, would you have taken such a vow?” If he replies, “Had I known, I would not have vowed,” then his vow is annulled.

Nedarim 9:5

An opening to annul a vow can be made for a man from his wife’s kesubah. There was once a man who vowed, prohibiting himself to benefit from his wife, which would compel him to divorce her, and she had a kesubah worth 400 dinar. They went to Rabbi Akiva, who ordered the man to pay the kesubah. The man balked, saying “My father left 800 dinar, of which my brother took 400! Wouldn’t it be enough to give her 200 and leave me with 200?” Rabbi Akiva told the man that he had to pay his wife the full 400 even if doing so meant selling the hair off of his head. He replied, “If I had known this was going to happen, I never would have made such a vow!” Rabbi Akiva then voided the vow.