Rental shops built with interest money on lawfully acquired land

Question

Question: Zayd, on a plot acquired with his lawful (halal) earnings, built shops for rent with interest money, and he lives on their income. Is this permissible or not? In the case of paying out the interest amount, is its income permissible or not? If not, what is the way to make it permissible? If you present some proof, it will be a true kindness.

Answer

Whatever amount of interest he has taken, let him return that same amount to the people from whom he took the interest; or, if returning it is difficult and those people are not known, let him give that same amount in charity (sadaqa) to the poor. Then (?) everything that was earlier (?)

Source: Fatawa Mahmudiyya

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