Getting rid of money taken without right by donating it for the construction of the mosque

Question:
And I said, O Shaykh, may Allah preserve you, I have money that I took without right, and its amount is four thousand riyals. So either I do not remember a period of time during which I paid it to help in building the mosque, or I do not know. Does this clear my conscience? And should I give charity from my salary every month to the owner of this wronged amount?

Answer:
If you do not know its owner, then you dispose of it and the good is purified, and its reward belongs to its owner. And if you paid it as a ransom, then he has the reward in that, and there is no harm. Yes. And I said, regarding the other matter, may Allah grant you success, because if it is purified, if it is good money from good earnings, that is fine. But if it is from a foul source, like riba (usury or interest), and you know that it is riba, then do not put it in the mosque. Put it in projects other than the mosque, general projects other than the mosque. Yes.