Nedarim 3:3-4

Nedarim 3:3

An example of a vow of compulsion is if one vowed against his friend to make him come for a meal and the guest was unable to attend because he got sick, or his son got sick, or a river prevented him. These are examples of things that are beyond his control.

Nedarim 3:4

One may make a vow to a murderer, a thief or a tax collector that something is terumah even when it isn’t or that they are members of the king’s household even when they aren’t. Beis Shammai say that one may make any type of vow in such a situation except for an oath; Beis Hillel say that one may even take an oath. Beis Shammai say that one may not volunteer to take a vow in such a case; Beis Hillel say that one may even volunteer to take a vow. Beis Shammai say that one may only vow the things that the antagonist compels him to vow; Beis Hillel say that one may even vow things he was not compelled to vow. For example, if bandits told him to say, “Konam my wife benefitting from me” and he said, “Konam my wife and sons benefitting from me.” In such a case, Beis Shammai say the wife is permitted and the sons are prohibited, while Beis Hillel say that even the sons are permitted.