Nedarim 90B

למימרא דלא הוה ביה מעשה.

That is to say that there was not yet any action but only speech, and even so the halakhic authority can dissolve the vow.

מיתיבי: ״קונם שאיני נהנה לפלוני ולמי שנשאל עליו״⁠ — נשאל על הראשון, ואחר כך נשאל על השני. אמאי? אי בעי ⁠— על האי ניתשיל ברישא, ואי בעי ⁠— על האי ניתשיל ברישא!

The Talmud raises an objection against this version of the tannaitic dispute from the aforementioned baraita: If one says: The property of so-and-so is konam for me, and for that reason I will not benefit from it, and deriving benefit from he who I will request dissolution for the vow is also konam for me, if he desires to dissolve the vows he must first request dissolution with regard to the first vow, and afterward he can request dissolution with regard to the second. But according to what was stated above, that all agree that a vow can be dissolved even before it has taken effect, why is this so? If he so wishes, he can first request dissolution with regard to this vow, and if he wishes, he can first request dissolution with regard to that one.

מי יודע הי ראשון והי שני?

The Talmud answers: Does he know which vow is first and which is the second? The wording of the baraita is not at all clear on this point. Perhaps, if he so wishes, he can first request dissolution of the vow not to derive benefit from the halakhic authority from whom he will request dissolution of his vow.

מתיבי: ״קונם שאיני נהנה והריני נזיר לכשאשאל עליו״⁠ — נשאל על נדרו, ואחר כך נשאל על נזרו. ואמאי? אי בעי ⁠— על נדרו ניתשיל ברישא, ואי בעי ⁠— על נזרו ניתשיל ברישא! תיובתא.

The Talmud raises a further objection from the second baraita cited above: If one says: The property of so-and-so is konam for me, and for that reason I will not benefit from it, and I am hereby a nazirite for when I will request dissolution of this vow, if he desires to dissolve the vows he must first request dissolution with regard to his vow that rendered benefit from a particular person forbidden, and afterward he can request dissolution with regard to his vow of naziriteship that he accepted upon himself should he request dissolution of his first vow. But why must he proceed in this manner? If he so wishes he can first request dissolution with regard to his vow not to derive benefit from that other person, and if he wishes he can first request dissolution with regard to his vow of naziriteship. The fact that the baraita does not say this indicates that a vow can be dissolved only once it has gone into effect. The Talmud concludes: Here is a conclusive refutation of this version of the dispute between R' Natan and the Rabbis.