Background: Concubinage may be defined as the more or less permanent cohabitation (outside the marriage bond) of a man with a woman or women, whose position would be that of secondary wives, women bought, acquired by gift, captured in war, or domestic slaves.

And whoever of you cannot afford to marry the independent believing women, then from those committed to you by oath of the believing maidens. God is more aware of your faith, you are to each other (i.e. equal)*. You shall marry them with the permission of their guardians and give them their dowries in kindness; they should be chaste not those who commit immorality and not those who take secret lovers. Then when they become protected/married, then any of them who comes with lewdness shall have half the punishment of what is for the independent women. This is for those who fear hardship from among you. But if you are patient it is better for you, and God is Forgiver, Merciful. [4:25]
*see 3:195 in which this exact phrase is also used, emphasising equality amongst genders in terms of faith and good deeds.

This passage lays down in an unequivocal manner that sexual relations with female slaves should only be permitted on the basis of marriage, and that in this respect there is no difference between them and free/independent women; consequently, concubinage is ruled out. Also see 5:5.

Also see the misconception Islam and The Quran promotes slavery.

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