Have you not considered the chiefs of the children of Israel after Musa, when they said to a prophet of theirs: Raise up for us a king, (that) we may fight in the way of Allah. He said: May it not be that you would not fight if fighting is ordained for you? They said: And what reason have we that we should not fight in the way of Allah, and we have indeed been compelled to abandon our homes and our children. But when fighting was ordained for them, they turned back, except a few of them, and Allah knows the unjust.

So when you meet in battle those who disbelieve, then smite the necks until when you have overcome them, then make (them) prisoners, and afterwards either set them free as a favor or let them ransom (themselves) until the war terminates. That (shall be so); and if Allah had pleased He would certainly have exacted what is due from them, but that He may try some of you by means of others; and (as for) those who are slain in the way of Allah, He will by no means allow their deeds to perish.

And what reason have you that you should not spend in Allah's way? And Allah's is the inheritance of the heavens and the earth, not alike among you are those who spent before the victory and fought (and those who did not): they are more exalted in rank than those who spent and fought afterwards; and Allah has promised good to all; and Allah is Aware of what you do.