A better question is why would an all knowing God create him in the first place? He has caused nothing but trouble for the human race. Can you imagine God setting around before he created the angels knowing full well the consequence of his actions, deciding to create an angel who would rebel, create weak humans who would follow this rebellious creature, end up in Hell for all eternity. And say to himself, what a great idea! This makes God look like some bumbling fumbling bored Nero who decides what a great idea it would be to burn Rome. It is fantasy tales like this that makes me question the very existence of a God, a devil, angels, etc. God has done way too many things throughout the bible that makes him look more and more like a deranged human than the all wise loving father we are told he really is.