Marry his mother-in-law

Q: I am a man who has a grown up daughter. I want to marry her off to a man who married my mother twenty years ago, then divorced her. Is it permissible for my daughter to marry this man? We appreciate your advice. May Allah guide you!

A: It is not permissible for you to marry your daughter off to a person who had married your mother if he had consummated the marriage with her before he divorced her. In that case, your daughter will be his step-daughter, and it is unlawful for him to marry her as mentioned in the saying of Allah (Exalted be He): ...your step daughters under your guardianship, born of your wives to whom you have gone in i.e. the daughters of the wife and her daughter's daughters and their descendants. (Part No. 18; Page No. 221) May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.