Allah is not a relationship God. He simply cannot be the friend or father of parent of anybody. Not Jesus, not Muhammad, not anybody. Allah is stated not to be a father 111.3. This is important for in those days parents died young and many fathers adopted their children. So it is not about biological fathers only. Christians say that God is our father in adoption. 5:18 is clear that Allah punishes all for their sins so that means nobody can say they are his children. Allah commands, "Say you are human beings from among the creatures he has created." Never say, "We are the children of God and his beloved." The implication is that claiming to be children of God is unnecessarily divisive and arrogant.