4:22Do not marry women whom your fathers married, except what is already past. That is improper, indecent, and a bad custom.

4:24And all married women, except those you rightfully possess. This is God’s decree, binding upon you. Permitted for you are those that lie outside these limits, provided you seek them in legal marriage, with gifts from your property, seeking wedlock, not prostitution. If you wish to enjoy them, then give them their dowry—a legal obligation. You commit no error by agreeing to any change to the dowry. God is All-Knowing, Most Wise.

4:25If any of you lack the means to marry free believing women, he may marry one of the believing maids under your control. God is well aware of your faith. You are from one another. Marry them with the permission of their guardians, and give them their recompense fairly—to be protected—neither committing adultery, nor taking secret lovers. When they are married, if they commit adultery, their punishment shall be half that of free women. That is for those among you who fear falling into decadence. But to practice self-restraint is better for you. God is Most Forgiving, Most Merciful.