And it does not behoove a believer to kill a believer except by mistake, and whoever kills a believer by mistake, he should free a believing slave, and blood-money should be paid to his people unless they remit it as alms; but if he be from a tribe hostile to you and he is a believer, the freeing of a believing slave (suffices), and if he is from a tribe between whom and you there is a convenant, the blood-money should be paid to his people along with the freeing of a believing slave; but he who cannot find (a slave) should fast for two months successively: a penance from Allah, and Allah is Knowing, Wise.

And he went into the city at a time of unvigilance on the part of its people, so he found therein two men fighting, one being of his party and the other of his foes, and he who was of his party cried out to him for help against him who was of his enemies, so Musa struck him with his fist and killed him. He said: This is on account of the Shaitan's doing; surely he is an enemy, openly leading astray.