Carrying someone's name other than the father

Q: When my nephew was young, his father passed away. Later on, his mother married another man and she and the child traveled with the new husband to Kuwait as he was working there. In good faith, this man changed the family name of my three-year-old nephew to his name. My nephew, who now belongs to the other man, graduated and is working in Kuwait. However, in Saudi Arabia he issued an identity card bearing his real name. Among people he is known by his real name, but the other official papers carry his second name.First, is he sinful? He has no choice concerning this matter and his work may be threatened if he changes his name.Second, he proposed to my daughter who accepted him, and her mother and I also accepted him. (Part No. 11; Page No. 485) Since all his work documents in Kuwait carry the second name, we are obliged to contract the marriage using this name. Is this act permissible? May Allah reward you.

A: It is obligatory upon your nephew to change his name to the one that is written on the identity card. It is impermissible for a Muslim to name himself after anyone other than his real father. This is reported in an authentic Hadith as well as in the Saying of Allah (Glorified be He) that states: Call them (adopted sons) by (the names of) their fathers Also, he should not use the official documents that go against Shari`ah (Islamic law) on the pretext that he was helpless when he made them as he was under age.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.