Study Bava Metzia folio 29B with parallel Hebrew-English text, traditional commentary, and modern study tools. Free access to Babylonian Talmud online.
The Talmud answers that the statement in the Mishnah: Therefore, if the money is lost, he is liable to pay restitution for it, can be explained in accordance with the statement of Rabba, as Rabba says concerning another Mishnah (58a): When the tanna says that they were stolen, the reference is to a case where the item was stolen by armed bandits; when he says that they were lost, the reference is to a case where the agent’s ship sank at sea.
אמר רב יהודה אמר שמואל: הלכה כרבי טרפון. ביד רחבה (הוה ליה) [הוו] הנהו זוזי דיתמי, אתא לקמיה דרב יוסף, אמר ליה: מהו לאשתמושי בגוייהו? אמר ליה: הכי אמר רב יהודה אמר שמואל: הלכה כרבי טרפון.
Rav Yehuda says that Shmuel says: The halakha is in accordance with the opinion of R' Tarfon, who said that it is permitted for the finder to use the money. The Talmud relates: There were these dinars that belonged to orphans that were in the possession of Raḥava. Raḥava came before Rav Yosef and said to him: What is the halakha; is it permitted for me to use these dinars? Rav Yosef said to him: This is what Rav Yehuda says that Shmuel says: The halakha is in accordance with the opinion of R' Tarfon.
אמר ליה אביי: ולאו אתמר עלה אמר רבי חלבו אמר רב הונא: לא שנו אלא בדמי אבידה הואיל וטרח בה, אבל מעות אבידה דלא טרח בהו – לא. והני כמעות אבידה דמו. אמר ליה: זיל לא שבקו לי דאשרי לך.
Abaye said to Rav Yosef: Wasn’t it stated concerning this halakha that R' Ḥelbo says that Rav Huna says: A baraita states this halakha, that it is permitted to use the money, only in a case of money received from the sale of a lost item that one found and that is no longer financially viable for one to tend to it. This is permitted, since he exerted himself and tended to it. But in the case of lost coins, where he did not exert himself in order to tend to them, it is not permitted for him to use them. And the case of these dinars in Raḥava’s possession is similar to a case of lost coins. Rav Yosef accepted Abaye’s objection and said to Raḥava: Go; as they did not allow me to permit the use of the dinars for you.