What is the ruling on the work of a legal consultant who authenticates real estate purchase and sale contracts, knowing that some buyers may borrow from interest-based (usurious) banks? What is the ruling on advising a friend to take an interest-based loan to buy a home due to the unavailability of Islamic banks? Is it permissible to deposit money in an interest-based bank without taking the interest?

The work of a preacher in documenting contracts and brokering is permissible if the contracts are Islamically permissible and the fee is known.

However, if he knows that the buyer will take an usurious loan to purchase the house, it is not permissible for him to endeavor to complete the contract, due to Allah’s saying: "And do not cooperate in sin and aggression." It is better not to ask the buyer to borrow with usury, based on the Prophet’s (peace be upon him) saying: "And whoever calls to misguidance will bear a sin similar to the sins of those who follow him."

But if he does not know about it, then there is no harm in his mediation in buying and selling, because the loan enters into the possession of the borrower after he seizes it. The borrower incurs sin for dealing with usury, and he must repent.

It is not permissible to deposit money in an usurious bank except when there is fear of loss, and the usurious interest must be disposed of.