פירוש על בבא מציעא 3:3

אמר לשנים: גזלתי לאחד מכם – And they do not make a claim against him at all, but he wants to fulfill [his responsibility] according to heaven.

If a man said to two others, “I have robbed one of you 100 zuz and I do not know which of you it is”, or “The father of one of you left me 100 zuz and I do not know whose father it was”, he must give each of them 100 zuz, since he himself admitted liability. In this mishnah the person speaking knows that he owes one of two people 100 zuz (a coin), either because he robbed one of them or because one of their father’s deposited 100 zuz with him. According to the mishnah he must give each of them 100 zuz, since he admitted his liability. If he had not done so, he would not have been obligated to pay either of them until one could conclusively prove that he had stolen from him or that his father had deposited from him. However, if he wants to fulfill his full moral obligation he needs to pay them both 100 zuz.

נותן לזה מנה ולזה מנה – but two who make claim and he admits that the stole from one of them, every one takes an oath that he stole from him. The Sages imposed a fine upon him because he translated on לא תגזול/”you shall not commit robbery” (Leviticus 19:13); and similarly, two who make a claim against one, each one says: “My father deposited with you a Maneh.” And he states: “The father of one of you left with me a Maneh but I do not know which one [of you];” each one of them swore that his father left with him a Maneh, and he gives a Maneh to this one and a Maneh to that one. For he had committed an act of negligence against himself for he should have paid attention and to remember who left with him the Maneh.