Talmud - Nedarim 23a נדרים כ״ג א׳

and the Sages were troubled by the fact that they could not dissolve the vow. They spent an extended period of time attempting to do so. During this time, they moved from a location with light from the sun to one with shade, and then moved again from the shade back to the sun.

The Gemara cites another version of the incident: They asked him: Did you vow with knowledge of this particular fact when you vowed? He said to them: Yes. This occurred several times and the Sages were troubled with this problem for an extended period of time, during which they moved from the sun to the shade and from the shade to the sun, but they did not find a solution.

Botnit, son of Abba Shaul ben Botnit, said to him: Would you have vowed with the knowledge that the Sages would be troubled even to the point of going from shade to sun and from sun to shade? He said: No, and they dissolved it.

The Gemara relates another incident: Rabbi Yishmael bar Rabbi Yosei had a vow to dissolve. He came before the Sages. They said to him: Did you vow with knowledge of this particular fact? He said to them: Yes. They asked again: Did you vow with knowledge of this other fact? He said to them: Yes. This occurred several times. When a certain launderer saw that the Sages were troubled because Rabbi Yishmael caused them difficulty in successfully dissolving his vow, he hit Rabbi Yishmael with a launderer’s tool that he had in his hand. Rabbi Yishmael said: Had I known that the launderer would hit me due to my vow I would not have vowed, and he dissolved it.

Rav Aḥa of Difti said to Ravina: This is a case of a new situation, which is not included among those matters that he could have considered at the time of the vow, because it would not enter his mind that the launderer would hit him. And we already learned: We do not broach dissolution with a person using a new situation that did not exist at the time of the vow. Ravina said to him: This is not a new situation that he could not have thought of previously, since it is common to find heretics [appikurei] who deny fundamental Torah principles and who trouble the Sages. Although he would not have considered the possibility that this launderer would attack him, he may have considered the possibility that some heretic would. Therefore, it was permitted to broach dissolution in this manner.

§ The wife of Abaye had a certain daughter. Abaye said: She should get married to my relative. His wife said that she should get married to her relative. He said to his wife: Benefit from me should be forbidden to you, if you defy my will and marry her to your relative. She went and defied his will and married her to her relative. Abaye came before Rav Yosef. Rav Yosef said to him: If you had known that she would ultimately defy your will and marry her to her relative, would you have made the vow? He said: No. And Rav Yosef dissolved the vow for him because Abaye did not think that his wife would actually defy him, and he intended the vow only to serve as a threat.

The Gemara asks: And is it dissolved in a case like this, where the vow was dependent on the daughter not marrying the wife’s relative? The Gemara answers: Yes, and it is taught in the Tosefta (5:1): There was an incident involving one man who vowed, prohibiting his wife from benefiting from him if she were to ascend to Jerusalem for the pilgrimage Festival, and she defied his will and ascended to Jerusalem for the pilgrimage Festival. And when he came before Rabbi Yosei to request dissolution, Rabbi Yosei said to him: And had you known that she would defy your will and ascend to Jerusalem on the pilgrimage Festival, would you have vowed at all? He said to him: No, and Rabbi Yosei dissolved it. This incident indicates that it is permitted to dissolve a vow with such an opening.

MISHNA: Rabbi Eliezer ben Ya’akov says: Even one who wants to take a vow prohibiting another from benefiting from him, but only in order that he should eat with him, not intending to take an actual vow, should say to him at the outset: Any vow that I take in the future is void. And this statement is effective, provided that he remembers at the time of the vow that his intent at the beginning of the year was to render it void.

GEMARA: With regard to Rabbi Eliezer ben Ya’akov’s proposal, the Gemara asks: And since he said: Any vow that I take in the future should be void, the one being invited will not listen to him and will not come to eat with him, since he already knows that the vow is not valid. That being the case, why would the first individual take a vow at all?

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

Nedarim 23a explores rabbinic efforts to annul vows through hypothetical regret, including cases involving unforeseen events like a laundryman's blow.