Sanhedrin 24B

מאי לאו באותן הנשבעין ולא משלמין, דהוה ליה כ״מחול לך״?

What, is it not referring to those who take an oath and do not pay, i.e., cases where the defendant is obligated to take an oath that the claim against him is false, and he is thereby exempt from paying? Accordingly, it is the claimant who suggests that the defendant take a vow instead, which is the same as saying: If you take a vow, the money I claim you owe is forgiven you.

לא, באותן הנשבעין ונוטלין, דהוה ליה כ״אתן לך״.

The Talmud rejects this objection: No, it is referring to those who take an oath and collect a debt. There are cases where it is the claimant who is obligated to take an oath, and he then collects the money that he claims. In a case where the defendant suggests that the claimant take a vow instead, it is the same as saying: If you take a vow I will give you what you claim.

והא תנא ליה רישא!

The Talmud challenges: But according to Rava’s interpretation, the Mishnah already taught the halakha in a case where the defendant says: I will give you, in the first clause, where the defendant accepts unfit judges.

תנא תולה בדעת אחרים, ותנא תולה בדעת עצמו.

The Talmud answers: The Mishnah taught in the former clause a case where the defendant makes the outcome dependent on the decision of others, namely, his father or the father of the claimant; and the Mishnah taught in the latter clause a case where he makes the outcome dependent on the claimant’s own decision.

וצריכא, דאי תנא תולה בדעת אחרים ⁠– בהא קאמר רבי מאיר דמצי הדר ביה, משום דלא גמר ומקני, דאמר: ״מי יימר דמזכי ליה?״ אבל תולה בדעת עצמו, אימא מודי להו לרבנן.

And it is necessary for the Mishnah to teach both cases, since if the Mishnah taught only the case where he makes the outcome dependent on the decision of others, one might reason that specifically in this case R' Meir says that he can retract his acceptance of the unfit judges. This is because he presumably did not resolve to transfer the money if these judges deem him liable, as he must have said to himself: Who will say that the judges will rule in favor of the claimant? But in a case where he makes the outcome dependent on the claimant’s own decision by suggesting that he take a vow, say that R' Meir concedes to the Rabbis that the defendant cannot retract his commitment to pay.