How a Mortgage Works in Contemporary Western Finance

An Islamic bank gives you a portion of the money that you need, whatever the remainder is. But then you and the bank become co-owners of that house. And what you do is you pay the bank rent for living in the house because you don't own the whole thing. The amount of rent that you owe also fluctuates with the value of the house. It goes up you owe more, it went down, it goes down. So what that means is that you and the banks are sharing the risk entirely.