Shevuot 28A

אפילו כל שהוא נמי!

Even if he had left any amount it would also be possible for him to dissolve the oath, as he had not yet broken his oath.

אי בעית אימא ״שלא אוכל״, אי בעית אימא ״שלא אוכלנה״. איבעית אימא ״שלא אוכל״⁠ – מיגו דמהניא ליה שאלה אכזית בתרא, מהניא ליה שאלה נמי אכזית קמא.

Rav Ashi answers: If you wish, say that the halakha stated by Rava is referring to a case where he took an oath, saying: I will not eat this loaf, and if you wish, say that it is referring to a case where he took an oath, saying: I will not eat it. The Talmud elaborates: If you wish, say that the halakha stated by Rava is referring to a case where he took an oath, saying: I will not eat this loaf. Since a request for dissolution is still effective even for the last olive-bulk of the loaf, it is effective also for the first olive-bulk.

ואיבעית אימא ״שלא אוכלנה״⁠ – אי שייר כזית, חשיב לאיתשולי עליה; ואי לא, לא חשיב לאיתשולי עליה.

And if you wish, say that the halakha stated by Rava is referring to a case where he took an oath, saying: I will not eat it. If he left an olive-bulk, that is a sufficiently significant quantity for which to request dissolution of the oath. But if he did not leave that much, it is not a sufficiently significant quantity for which to request dissolution of the oath.

מיתיבי: מי שנדר שתי נזירות, ומנה ראשונה והפריש עליה קרבן, ואחר כך נשאל על הראשונה ⁠– עלתה לו שניה בראשונה!

Rava assumes that once one has eaten the entire loaf, it is no longer possible to dissolve the oath. The Talmud raises an objection to this from a baraita: With regard to one who took two vows of naziriteship, and counted the first term and separated an offering for it, and afterward requested and received dissolution of the first vow from a halakhic authority, the second term was counted for him in the observance of the first term and he is not required to be a nazirite further. Although the first term of naziriteship was entirely finished, a halakhic authority could still dissolve the vow.