Abu Dharr states that he heard the Prophet, may Allah bless him
and grant him peace, say, "A person who knowingly claims a father other
than his own has disbelieved. A person who claims to be from a people when
he is not one of them will take his place in the Fire. A person who calls
a man an unbeliever or says, 'Enemy of Allah,' when that is not the case
will have that come back on him."