Siman 136

One whose vessels were switched in a craftsman's house, where he gave the craftsman his vessel or garment to repair and afterwards came to the craftsman to receive it, and he said to him, "Here is a tallit or vessel," and he received it and left and found that it was not his, he may use them until the owner of the vessel comes and takes his own. For we hang the matter on the possibility that another person gave his tallit or his vessels to the craftsman to sell them, and the craftsman erred and sold this person's instead of it, and when this person came and asked for his tallit from the craftsman, he realized he had erred and gave him in its place the tallit of the other who commanded him to sell. Thus, there is no "use without knowledge" here. And one should not say: nevertheless, how can he use it through the craftsman's delivery? For if the buyer is not satisfied with this person's tallit when he exchanges it, he can return the tallit, and it will turn out that he used the seller's tallit without his knowledge. For it can be said that since the seller was pressed for money and sold his tallit, he is not meticulous if others use it, as he also uses the money (Levush). And this is specifically when the craftsman himself gave it to him, for he is like the agent of the seller, and the use is as if with the knowledge of the seller. But if his wife or children gave it to him, he may not use it, for they do not have permission to give it for use. And even the craftsman himself, specifically when he said to him, "Here is a tallit," without specification, for in this we hang the matter as has been written; but if he said to him, "Here is your tallit" or "your vessel," it is forbidden to use it, for it appears that he erred, and it is forbidden to use without knowledge. And if the tallit that the craftsman gave him is worth more than his tallit, the choice is in his hand: either to give the owner of the tallit the surplus, or to return his tallit to him and receive from him the money that the craftsman gave him, and he shall claim from the craftsman that he return the buyer's money and receive his tallit. And if his tallit is worth more, he can receive the surplus from the owner of the tallit or cancel the sale. And if the owner of the tallit comes and says, "I did not command the craftsman to sell it, nor did I take money from him," he is believed to take his tallit from the hand of this person if he has witnesses or gives a sign on the tallit that it is his. For although we hang the matter on saying that he commanded him to sell it, nevertheless, if he claims that he did not command him to sell it, he is believed (Tur) even without an oath, since this person admits that it is not his, and he shall seek out the craftsman to receive his tallit or his money. And even if he does not receive it from the craftsman, he may not withhold the tallit of this person. And if the craftsman denies the owner of the tallit, let the law pierce the mountain between them.

If his garments or his objects were switched in a house of mourning, or in a house of feasting, or in a beit knesset, or in other places—for example, if he took his garments or his objects and saw afterward that they are not his—he may not use them. We do not hang the matter on the assumption that the owner of the object took his own and is using it, and that he too may use this object, as we hang the matter in the case of a craftsman. For with a craftsman there is a basis for the matter, as he did not say to him "here is your cloak," as has been explained. But when it is known that they were switched by mistake, we do not say so, for perhaps the owner of the object did not take his own, and even if he took it, perhaps he would not be pleased to use it. Therefore, when the owner of the object comes, he must return his object to him even though his own is lost. And so too a laundress who washes for many and brought to one person objects that are not his, it is forbidden to use them, and he must return them to their owners even though his own are lost. And in similar cases regarding all things, Reuven may not withhold Shimon's objects because his own were lost, for what is Shimon's liability in this? And if the objects are with him for several days and the owner of the objects did not come to claim them, it is possible to hang the matter on the assumption that the owners despaired of this, or that the laundress paid the owners, or that the objects are hers and she intentionally gave them to this person whose objects were lost with her and gave him these in their stead (see Turei Zahav). And the custom in large places, a place where many gather and leave their overshoes in the corridor and upon their exit they are switched one for another, they are not fastidious about the matter, and each one uses those of his fellow until they see each other and switch back, and there is no concern of theft in this, for such is the custom.