Amatul Rahmân Omer:
And (you are also forbidden to marry) already married women who are in a wed-lock. Yet those (captives in war) whom your right hands possess (are permitted to you for marriage even if not formally divorced by their former husbands, since their captivity is equivalent to divorce). This is the law prescribed to you by Allâh. All (women) beyond those (mentioned above) are lawful to you, provided you seek (their hands) by means of your wealth (- by granting dowers), marrying them properly and not (committing fornication) to pursue your lust. You shall, for the benefits you draw from them (by regular marriage), pay them (- your wives) such of their dowers as have been fixed. There is, however, no blame on you (in increasing or decreasing the amount of dower) which you (- husband and wife) mutually agree upon, after it has been (once) fixed. Surely, Allâh is All-Knowing, All-Wise.