Is it allowed to eat or drink in a house which owner works in a usurious institution because his money is considered haram?

Answer

Praise Be to Allah and Peace Be Upon His Messenger.

It is preferred to advise a person who works in usurious institutions such as banks to quit their job. Usury is considered one of the heinous sins. It is also a reason for not responding to your supplications. The prophet says: “Allah is Pure and He accepts only what is pure.” Then he mentions – at the end of his saying- a man who makes a long journey in a disheveled and a dusty state who stretches out his hands to the heaven saying, “My Lord, my Lord,” while his food is haram (unlawful), his drink is haram and his clothing is haram, and he has been nourished with haram, so how can his supplications be answered?”

However, if you eat or drink something which was originally bought by your father in law who works in the usurious bank, and you were a guest, then, you are not sinful because it is not you who got that kind of money.

The impure gain such as the money that one gets by cheating or by any illegal method is considered unlawful to the one who gets it only, but it is not haram for guests who are served foods or drinks. In other words, the owner of the money is sinful, but you are not. The evidence for this is that Prophet Muhammad (PBUH) used to deal with the Jews who used to devour what is unlawful and get interests.