Siman 355

One who steals an object from the house of his fellow and returned it to its place, and the owners did not know that he returned it: if the owners knew of the theft, he is not exempt by his returning it without the owners' knowledge, and it remains under his responsibility until they become aware of its return, such as if he counts his objects and finds them complete. For since they knew it was stolen, they have despaired of guarding it further, and when he returned it, he does not know of this so that he may guard it. Therefore, when it becomes known from this even after its return, such as if he counted the vessels and found the stolen vessel among them, even though they did not know at the time of the return, he is exempt from responsibility, and knowledge at the time of the return is not a requirement. Therefore, Reuven who stole money from Shimon and included it for him in an account and placed them into his purse, he has fulfilled his obligation because a person is prone to feel his purse at all times, and consequently he will become aware of this and find that he returned it to him among his money. And some say that the one returning it must know that this one knows the count of his money, but when he does not know that this one knows, this is not a restoration, as it is possible that he will never become aware of its return. And so too, if the one returning it threw them into his purse which has nothing in it, he has not fulfilled his obligation and is liable for the responsibility of the theft until he informs him that he returned it to such-and-such a purse. And if the owners did not know that it was stolen from them, immediately when he returned them to their place, he has fulfilled his obligation even though the owners did not count them, for he did not remove his guarding from them since he did not know at all of the theft. [See Sma who raised a difficulty regarding the Shulchan Aruch who combined two opinions, and it appears to me that he holds that the Rambam also admits that he must know the count of the money, and the Tur also admits in the case of returning to an empty purse. And the Rambam would explain that which is stated in Bava Kamma 118a: this is where he has other coins and knows how many, and this is where he does not have, etc. And Rashi explains: where he has and does not know how many, and where he does not have and uses the purse constantly. And according to this, they do not disagree in the ruling, and examine this]:

That which has been explained, that when the owners were unaware, its return is more lenient than when they were aware—to what does this apply? To an object that does not possess a life-force. However, regarding an object that possesses a life-force, on the contrary, its return is more stringent when they were unaware than when they were aware. For when they were aware, counting it exempts him as with an object that does not possess a life-force, but when they were unaware, counting it is not effective until he informs the owners that it was stolen and returned. Because this living creature has become accustomed to leaving its place, it requires superior guarding more than before; therefore, the owners must know of the theft and the return so that they may guard them from now on with superior guarding.

Therefore, one who steals a lamb from the flock and the owners knew of the theft, his law is as in section 1, that if he returned it to the flock without the knowledge of the owners and it died or was stolen, he is liable for its responsibility. And if after the return the owner counted the sheep and found them complete and knew that it was returned, he is exempt even though he did not know at the time of its return, for since he knew it was stolen, he will guard it from now on with superior guarding. But if they knew neither of its theft nor of its return, even though they counted the sheep and it is complete, he is liable for its responsibility until he informs the owners of the theft so that they may guard the stolen lamb with superior guarding. And if this lamb that was stolen is marked and recognizable in the flock, such as if it is speckled and spotted, he is exempt from responsibility upon its return even before they counted the sheep, provided only that they knew of the theft, for it is recognizable on its own and presumably the owners saw it immediately, and it is like money which one is likely to feel in his pocket at every hour [Sma]:

And that which has been explained, that regarding a thing which does not have a life-spirit one is exempt by returning it to its place without counting, in what case are these words said? Regarding a thief who steals from the house of the owners. But a shomer who stole from his own domain—for example, if some object or a pouch or a living creature was deposited with him and he misappropriated it and stole it, and then returned it to its place and guarded it as before—he is liable for the responsibility of accidents until he informs the owners that he misappropriated it and returned it. And then, if the owners agree that he should remain a shomer as before, he shall be exempt from accidents. For if he did not inform them, behold his guardianship has ended, and it is as if he did not return it; for we assess the mindset of the depositor, that certainly it is not his will to make him a shomer over this after he misappropriated the deposit.

The Rambam and the Tur wrote that a guardian who stole from his own domain and there are witnesses that he stole it, even though there are witnesses that he returned it to its place, he is liable for its responsibility until he informs the owners. Thus far their words. The poskim inferred from this that specifically when there are witnesses to the theft do we say that he is removed from his guardianship; but when there are no witnesses to the theft and he returned it of his own accord, he has performed repentance of his own will, and we say that it is pleasing to the owners that he should still be the guardian, and the return is sufficient even without the knowledge of the owners, even in the case of a living creature, for in this the reason of "superior guarding" is not applicable since he is guarding it and knows of the theft [Sma and Bach]. And there are those who disagree on this [Shach]. And it has already been explained in siman 292, section 9, that from the words of our teacher, the Rema, there, it appears that he also holds of this distinction; see there.

The opinion of the Rambam in the fourth chapter of Laws of Theft is that a shomer who stole from his own domain and there are witnesses to the matter is liable to pay kefel. And even though one who performs shiluchut yad with a deposit is exempt from kefel, nevertheless when he stole it he is liable. The Ra'avad disagrees with him, for there is no kefel for a shomer except when he claims the plea of a thief and swears and witnesses come, but without an oath he is not liable for kefel [the Maggid Mishneh]. And the reasoning of the Rambam, it can be said, is that specifically when the deposit is in its place and he claims the plea of a thief is he only liable for kefel through an oath, but when he actually stole it, his law is like any other thief and he is liable for kefel when witnesses come [Kesef Mishneh]. [And from the sugya of the Shas in Bava Kamma 63b, one should not raise a difficulty, for since this is like any other thief, a verse is not required, and note this carefully]: