Abu Dawud Book 30, Hadith Number 4261.

Chapter : Gravity of the sin of killing a beleiver.

Narated By N/A : The tradition mentioned above has also been transmitted by Sa’d b. Jubair from Ibn Abbas through a different chain of narrators. Ibn ‘Abbas said: The verse “Those who invoke not with Allah (Qur’an xxv. 68)” applies to polytheists. He said: About them another verse, “Say: O my servants who have transgressed against their souls (Qur’an xxxiv. 53)” was also revealed.