The Mythology & Folklore Database
Hereupon Adam told them to take their offerings to Allah, thereby referring the dispute to His determination. Cain's offering was a sheaf of the very worst of his corn, but Abel's a fat lamb of the best of his flock.
Allah having declared His acceptance of the latter in a visible manner, Cain said to his brother, "I will certainly kill you."
Abel was the stronger of the two, and would easily have prevailed against his brother, but he answered, "If you stretch forth your hand against me, to slay me, I will not stretch forth my hand against you to slay you, for I fear Allah, the Lord of all creatures."
So Cain began to consider in what way he should effect the murder, and as he was doing so, the devil appeared to him in human shape, and showed him how to do it, by crushing the head of a bird between two stones.
Cain, having committed the fratricide, became exceedingly troubled in his mind, and carried the dead body on his shoulders for a considerable time, not knowing where to conceal it, till it stank horribly. And then Allah taught him to bury it by the example of a raven, who, having killed another raven in his presence, dug a pit with his claws and beak and buried him therein.