But if he took a vow of naziriteship after his animal was stolen, he is not a nazirite, as it is retroactively established that his vow was taken in error from the outset, as he relied on an animal he did not possess. And this was the error that Naḥum the Mede erred when he failed to distinguish between an event that occurred before the vow was taken and an event that occurred afterward. The incident in question was as follows: When nazirites were ascending from the exile to sacrifice their offerings, and they found the Temple destroyed, Naḥum the Mede said to them: If you had known that the Temple would be destroyed, would you have taken a vow of naziriteship? They said to him: Certainly not, as there is no remedy for a naziriteship in this case. And Naḥum the Mede dissolved the vow for them.

And when the matter came before the Rabbis, they said: His ruling is incorrect. Rather, whoever took a vow of naziriteship before the Temple was destroyed, like these nazirites from the exile, he is a nazirite, as he committed no error at the time of his vow, and one cannot dissolve vows based a new situation. However, one who stated his vow after the Temple was destroyed is not a nazirite, as he vowed based on an erroneous assumption.

GEMARA: In relation to the mishna’s statement with regard to the dissolution of a vow of naziriteship due to a new situation, the Gemara cites a statement that Rabba said: The Rabbis overwhelmed Rabbi Eliezer until he retracted his ruling and established the halakha in accordance with their opinion. To what does this refer? As we learned in a mishna in Nedarim (64a): They may broach dissolution by asking about a new situation, i.e., a halakhic authority can dissolve a vow due to a new situation that the one who took the vow did not anticipate at the time he took his vow. This is the statement of Rabbi Eliezer; but the Rabbis prohibit this. Since Rabbi Eliezer does not disagree in the case of naziriteship in this mishna, he must have accepted the opinion of the Rabbis.

And Rava said, with regard to the same issue: Even though the Rabbis said that they may not broach dissolution by asking about a new situation, however, they may broach dissolution by asking about the conditions of a new situation, i.e., with situations similar to a new situation. What are the circumstances of this type of broaching dissolution? The halakhic authorities say to the nazirites who took their vows before the destruction of the Temple: If a person had come and said to you before you took your vow that the Temple will be destroyed, would you have vowed? Although the destruction of the Temple itself is a new situation, its potential occurrence existed when they vowed, and therefore if they answered that they would not have vowed had they known this, their vows are dissolved.

Rav Yosef said: If I had been there, when those nazirites arrived, I would have said the following to them, in order to dissolve their vows: Isn’t it written: “The Sanctuary of the Lord, the Sanctuary of the Lord, the Sanctuary of the Lord, are these” (Jeremiah 7:4). This thrice repetition of “Sanctuary of the Lord” is referring to the First Temple and the Second Temple which are destined to be destroyed, leading to a Third Temple. These nazirites should have considered the possibility of the Temple’s destruction, and this can serve as a means of broaching the dissolution of their vows.

The Gemara responds: Although they might have known that the Second Temple would be destroyed, as the verse speaks of three Temples, did they know when it would be destroyed? Would they have considered that it might occur in their lifetimes, preventing them from sacrificing their offerings? Abaye said: And did they not know when? But isn’t it written: “Seventy sevens are decreed upon your people and upon your sacred city” (Daniel 9:24), which indicates that the Second Temple would be destroyed seventy Sabbatical cycles of seven years after the destruction of the First Temple, which is 490 years. The Gemara answers: And still, did we know on which day it would be destroyed? It was therefore impossible to use this factor as a means to broach the dissolution of their vows.

MISHNA: If there were people walking along the way, and one other person was approaching them, and one of those walking said: I am hereby a nazirite if this person approaching us is so-and-so. And another one of them said: I am hereby a nazirite if this is not so-and-so, while a third member of the group said: I am hereby a nazirite if one of you two is a nazirite, and a fourth said: I am hereby a nazirite if neither of you is a nazirite, and another added: I am hereby a nazirite if both of you are nazirites. Finally, the last person said: I am hereby a nazirite if all you who spoke before me are nazirites.

Beit Shammai say that they are all nazirites, as by saying: I am hereby a nazirite, they have accepted naziriteship upon themselves even if their statements turn out to be incorrect. Beit Shammai maintain that a vow of naziriteship taken in error is considered a valid vow of naziriteship. And Beit Hillel say: Only he whose statement was not fulfilled is a nazirite. And Rabbi Tarfon says: Not a single one of them is a nazirite, including those whose statements were correct. Rabbi Tarfon maintains that a vow of naziriteship must be pronounced in an explicit manner, without any hint of uncertainty. In this case, none of them knew for sure the identity of the person coming toward them, and therefore they could not be certain they were nazirites at the time of their vows.

If the person approaching them turned back so that his identity was never discovered, not one of them is a nazirite. The matter was never clarified, and the halakha is lenient in cases of uncertain naziriteship. Rabbi Shimon says that the halakha is stringent with regard to an uncertainty of this kind, and therefore they should proceed as follows in order to avoid any uncertainty: Each of those who took a vow should say: If it was in accordance with my statement, I am hereby an obligatory nazirite, as my condition was fulfilled, and if not, I am hereby a voluntary nazirite, and in this manner they are all nazirites either way.

GEMARA: The Gemara questions the opinion of Beit Hillel: Why is he whose statement was not fulfilled a nazirite? Rav Yehuda said: One must emend the wording of the mishna so that it says: Only he whose statement was fulfilled becomes a nazirite.