A father calling his son a Kafir because he annoyed him

Q: What is the ruling if someone infuriates his father to the extent that the father says "You are a Kafir (disbeliever)"? Will the word Kafir revert to the father?

A: It is not permissible for a father when enraged by his son to call him a Kafir; he has to repent and seek forgiveness. It was authentically reported on the authority of Ibn `Umar (may Allah be pleased with them) that Allah's Messenger (peace be upon him) said, If a man says to his brother (in Islam), ‘O you Kafir (disbeliever)!’ one of them will deserve the title. Either the person addressed is so or, if not, it (the title of Kafir) will revert to him (the speaker). May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.