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.