י״ג באב ה׳תשע״ה (July 29, 2015)

Nedarim 66a-b: Dissolution of a Vow

One possible petah – i.e. grounds for dissolution of a neder – that is presented by the Mishna is Shabbat ve-Yamim Tovim. For example, a person who vows to refrain from eating meat can annul the vow if he agrees that he did not realize the problems that would ensue from his neder on Shabbat and holidays, when it is accepted that everyone eats meat.

The Mishna teaches that at first this was understood to be dispensation, which would allow the person to eat meat only on Shabbat and Yom Tov, even as the neder remained in effect on other days. Then Rabbi Akiva came and taught she-ha-neder she-hutar miklalo, hutar kulo: when part of a vow is dissolved, the entire neder is dissolved. The Talmud Yerushalmi explains this based on the pasuk in Bamidbar (30:3), according to which a person must keep everything that he expresses as a neder. Once he is not keeping part of it, however, he does not need to keep any of it.

The Ritva explains the case of the Mishna as one where, at the time of the neder, the person believed that his neder would not apply to Shabbat and Yom Tov. Once he is made aware of the fact that it will apply to those days as well, he uses that information as a petah to annul the vow. The Meiri suggests that the case of the Mishna is one where the person took the neder without thinking through all of the repercussions and without realizing that during the period of his vow there would be days when he could not keep the neder. Thus, the petah is that, had he realized that such days were included, he would never have taken the vow. Furthermore, argues the Meiri, we may be dealing with a situation where the person does not realize that he is obligated to eat on Shabbat and holidays, and when that is clarified to him, he declares that he would not have taken such a neder in the first place.