The gemara says that in regards to a thief or a guardian who returns an object, there must be an awareness on the part of the owner that his object has been returned. If he does not know, then the responsibility remains upon the thief or guardian if anything occurs to the object before the owner is indeed aware of its return.
This is not true, says the gemara, in regards to a lost object that is being returned. As long as it is returned to the domain of its owner, the owner need not be aware of it. The gemara proves this from the passuk השב תשיבם – the double language of returning teaches that one must even return the object many times.
The question is, what does one thing have to do with the other? How do we see from the fact that I must return it many times that I have less of a responsibility and even if the owner is unaware that his object has been returned I am no longer held accountable if anything happens?
Perhaps it could be explained, לע”ד, that when the Torah says השב תשיבם – that there is an obligation to return a lost object even multiple times – it is basically saying that even if the person who lost his animal has been irresponsible and not properly watched it on more than one occasion, the person who finds it would still have to return it over and over again. This basically means that the Torah does not focus on the irresponsibility of the person who has lost the object – as far as the Torah is concerned he is not careful and we don’t care! If you found it, you must still return it, despite the owner’s carelessnes, even a hundred times!
From the Torah’s view of the owner of the lost object, it is clear that his awareness of his object is not so significant in relationship to his responsibility for his own object. That being the case, there are two ramifications – 1. The one who finds it must return it multiple times, and 2. If it is returned to the (well-guarded) domain of its owner, he need not even be aware of it!
על דרך המוסר, what also comes out of this, is that if someone sees an object that is lost lying on the ground, even if one would tell himself that the owner will probably never claim it, one should still pick it up. The reason would be that even if the person doesn’t claim it, the obligation of the Torah to return an object is clearly not focused on the person who lost the object – rather on the person who has found the object! This is evident from the obligation to return the object multiple times – despite the owner’s negligence!