As we learned on yesterday’s daf, the situation of a mokhes – a tax collector – was different in Talmudic times than it is today. Tax collectors were individuals who purchased the right to collect taxes from the government and then could choose to collect different amounts from different people – a system that created anomalies and caused the Rabbinic Sages to consider a mokhes a dishonest person.
The Mishna on our daf teaches that if a person had his donkey or his cloak taken by a mokhes, but then received a different one from the mokhes in its stead, he can keep it, since we can assume that the original owner despaired of ever getting it back (referred to as ye’ush – despair).
The Gemara opens by quoting a baraita that teaches that when the person receives an object in exchange for his own from the mokhes, he should return it to the original owner. The explanation for this ruling would be that simple ye’ush does not suffice to allow for transfer of ownership. An alternative reading of the baraita suggests that although the recipient can keep the object because of the owner’s ye’ush, he would likely return it to the original owner, since a person does not want to keep property that does not really belong to him.
According to Rashi, the baraita (in either of its two presentations) stands in disagreement with the Mishna, which did not see any need to return the object. The Ra’avad disagrees, arguing that a baraita that is introduced with the term tanna immediately after a Mishna invariably comes to explain the Mishna, rather than argue with it. The Ra’avad explains that the baraita expects the recipient to return the object to its owner – but not for free. He can demand from the owner to pay him what he lost in his interaction with the mokhes.