The Jordan River - And this is the case for other rivers. This sage (teaching the Baraita) was sitting by the Jordan River.

Armed robber - He took it from him by force, and from the outset, the owner knew and despaired (of recovering it).

They are his, etc. - The correct text is: 'They are his, because the owners have despaired.' For anything swept away by a river, like beams of wood and stones, the owners immediately become aware of it because it is something that creates a commotion (is widely known)."

This is the default case - But if it were another type of lost item, where we cannot assume that the owners were aware [of the loss], it would not belong to the finder. This presents a difficulty for Rava.

Even if they are not chasing [after it], as well - because he relies on rescuing it tomorrow or the day after, and he does not despair [of recovering it].

Under pressure - And if they do not act quickly to rescue [the item], it will not be saved. Therefore, if they do not pursue it, as they have declared it ownerless, since they knew [of the loss] and did not save it.

Go to the better ones— you should have gone to the better ones to give from them to the priest.

He did not know—thus, since when he finds out, it is acceptable to him, we say that retroactively it was also acceptable to him. And regarding the matter of despair , since when he finds out he would despair, retroactively it is also considered despair.