Is it permissible to take back a loan from a man most of whose wealth is haraam?

Taking interest and offsetting losses with riba

Ruling on working in a centre that corrects exam papers that include subjects that are contrary to sharee‘ah

It is not permissible for your father to accept what is given to him because of his work

If a person takes haram wealth and invests it, is the profit permissible for him?

Taking a card and giving money to its owner and five other people, in a pyramid scheme

He is afraid that if he returns money that he stole before he was guided, he will be found out. What should he do?

His boss gave him the job of following up on some technical drawings, and he managed to save some money on that

Is it permissible for him to take the money left over by the students after a trip because he was not paid anything for supervising?

He is trying to get out of paying back to the property bank on the grounds that he has a right in the bayt al-maal