Money found in a purchased safe: whose property is it?

Question

Question: Two brothers, Zayd and ‘Amr, owned an iron safe, which both brothers, by mutual agreement, sold to Khalid after emptying it. Khalid left the safe with Zayd and ‘Amr, saying, “When I bring a handcart or the like, I will load it and take it away.” Several days passed. In the meantime someone told Khalid that he should also demand from the seller the lock that had been fitted to this safe, which both brothers had removed at the time of selling it, so that the safe would be complete.

Answer

The sale was of the safe, and of whatever is attached to it in such a way that it is not detached — for example a built-in lock — and also its key, since without the key the lock is useless. The seller had no knowledge at all of the money that had been lying in one of its compartments; rather, in his own view he had already emptied it and believed that there was now nothing in…

Source: Fatawa Mahmudiyya

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