Q: Is illicit gain in usurious loans limited to the interest rate, or does it include both the principal and the interest, and is the borrowed money itself considered permissible despite the prohibition of the act of borrowing?

A loan conditioned on an increase is forbidden and usurious by the agreement of scholars. The stipulated increase is evil and must be returned to the borrower along with repentance. The principal amount of the loan is permissible. The borrower incurs sin by agreeing to a usurious contract. If he disposes of the money, he must return its equivalent, but what he purchased with it is permissible. If he does not dispose of it, he must return it without any increase according to the majority of scholars, while the Hanbalis hold that he owns the money, though he incurs sin.