Quran 5:31 — The Feast (Al-Ma'edah)

GOD then sent a raven to scratch the soil, to teach him how to bury his brother's corpse. He said, "Woe to me; I failed to be as intelligent as this raven, and bury my brother's corpse." He became ridden with remorse.

[5:30] His ego provoked him into killing his brother. He killed him, and ended up with the losers.

[5:32] Because of this, we decreed for the Children of Israel that anyone who murders any person who had not committed murder or horrendous crimes, it shall be as if he murdered all the people. And anyone who spares a life, it shall be as if he spared the lives of all the people. Our messengers went to them with clear proofs and revelations, but most of them, after all this, are still transgressing.