An-Nisa 4:24 ۞ والمحصنات من النساء الا ما ملكت ايمانكم كتاب الله عليكم واحل لكم ما وراء ذالكم ان تبتغوا باموالكم محصنين غير مسافحين فما استمتعتم به منهن فاتوهن اجورهن فريضة ولا جناح عليكم فيما تراضيتم به من بعد الفريضة ان الله كان عليما حكيما ٢٤

Also (prohibited are) women already married, except those whom your right hands possess: Thus hath Allah ordained (Prohibitions) against you: Except for these, all others are lawful, provided ye seek (them in marriage) with gifts from your property,- desiring chastity, not lust, seeing that ye derive benefit from them, give them their dowers (at least) as prescribed; but if, after a dower is prescribed, agree Mutually (to vary it), there is no blame on you, and Allah is All-knowing, All-wise.