Capture of prisoners during war was the most common way of acquiring slaves. Prisoners would inevitably be captured during any war, and the prevalent custom at that time was that prisoners had no protection or rights; they would either be killed or enslaved. But Islam brought two more options: unconditional release or ransom. Allaah says (interpretation of the meaning): “Thereafter (is the time) either for generosity (i.e. free them without ransom), or ransom (according to what benefits Islam)” [Muhammad 47:4]. During the battle of Badr the Prophet (peace and blessings of Allaah be upon him) accepted ransoms from the mushrik prisoners of war and let them go, and the Messenger (peace and blessings of Allaah be upon him) let many of the prisoners go for free, releasing them with no ransom. During the conquest of Makkah it was said to the people of Makkah: “Go, for you are free.”
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