The Ruling on Mixing Forbidden Food With His Food

Question :

Some Muslims with us in Britain obtained their money from permissible sources and forbidden sources and this is because they are businessmen. Among the things in which they trade are alcohol and swine flesh; and they are on different levels in this regard: Some of them gain most of their wealth through what is unlawful, while others gain a small portion of their wealth from what is unlawful. Is it permissible for us, the Muslims, to mix with them and eat their food if they invite us? And is it permissible for us to accept the charity they give from this money for the maintenance of mosques?

Answer:

Firstly: you must advise them and warn them of the evil outcome of trading in forbidden goods and obtaining money from forbidden sources. You must cooperate with your brothers among the righteous folk in reminding them and warning them of Allah's Punishment and His severe Chastisement upon those who disobey Him, those who declare war against Him by committing sins. You must (cooperate) in reminding them of the fact that the enjoyment of the life of this world is but little, and that the life of the Hereafter is better and more lasting.

If they respond positively, then all praise and thanks be to Allah, and they are thereby your brothers in Allah's religion. Then advise them to return the rights which they unjustly took to their owners, if they know them, and to follow up evil deeds with good deeds, so that perhaps, Allah will turn to them with Forgiveness and replace their evil deeds with good deeds.

In that case, it would be permissible for you to mix with them as you would mix with your brothers, and eat from their food, and accept their charities given for righteous works, such as building and furnishing mosques and such like. By their repentance and returning rights to their owners as much as is possible, their previous sins are forgiven, according to the Words of Allah, the Almighty, the All-Powerful regarding those who deal in usury:
"So whosoever receives an admonition from his Lord and stops eating Riba, shall not be punished for the past; his case is for Allah (to judge)."

Secondly: If they refuse after being advised and being reminded, only to continue doing the forbidden things they are doing, then they must be avoided for Allah's sake. Then do not respond to their invitations, nor accept their charity, in order to reprimand them and rebuke their vain deeds, hoping that they will refrain from that and cease the evil they are involved in.

May peace and blessings be upon our Prophet, Muhammad and upon his family and Companions.

Source:
The Permanent Committee
Fatawa Islamiyah, Vol. 6 Pages 352-353