Is it permissible to pray in a mosque that is being renovated with funds from a usurious bank’s rent, which is a tenant of part of the mosque's property?

Firstly: It is impermissible to rent out a premise to someone who will use it for sin, such as an usurious bank, because it constitutes aiding in sin, and because the renter knows that the bank will engage in prohibited transactions. Al-Buhuti mentioned that it is invalid to rent a house to be used as a church or for selling alcohol or gambling, because these are prohibited acts. Those in charge of the mosque must terminate this forbidden contract and rent the space to a party that will use it for permissible purposes.

Secondly: Prayer in the mosque is permissible, and the sin falls upon those who deal with the bank. Efforts should be made to convince those in charge to keep the mosque free from ill-gotten money resulting from renting to the usurious bank. If they insist, the sin is theirs, and the prayer remains valid. The Permanent Committee has issued a fatwa permitting prayer in a mosque built with money mixed with usury or stolen money, with the sin falling upon the usurer and the thief.