Nazir 5:5-6

Nazir 5:5

Let’s say that six people were on a journey and someone approached them. The first says, “I am a nazir if that is person X.” The second says, “I am a nazir if that is not person X.” The others say, “I am a nazir if one of you is a nazir,” “if one of you is not a nazir,” “if both of you are nazirs” and “if all of you are nazirs.” Beis Shammai say that all of them are nazirs (because a mistaken vow still counts) while Beis Hillel say that no one is a nazir except for those whose conditions are met. Rabbi Tarfon said that nobody is a nazir (because one must know at the time of his vow whether or not he is in fact a nazir)

Nazir 5:6

If the person approaching the group turns back (so they never find out if it was person X or not), nobody is a nazir. Rabbi Shimon says that each one should say, “If my condition was met, I am a nazir out of obligation. If it was not, I am a voluntary nazir.”