Deuteronomy 21:10-17

¹⁰When you go out to do battle against your enemies and Yahweh your God gives you victory and puts them under your control, and you take them away as captives,

¹¹if you see among the captives a beautiful woman, and you have a desire for her and wish to take her for yourself as a wife,

¹²then you will bring her home to your house; she will shave her head and cut her nails.

¹³Then she will take off the clothes she was wearing when she was taken captive and she will remain in your house and mourn for her father and her mother a full month. After that you may sleep with her and be her husband, and she will be your wife.

¹⁴But if you take no delight in her, then you may let her go where she wishes. But you must not sell her at all for money, and you must not treat her like a slave, because you have humiliated her.

¹⁵If a man has two wives and one is loved and the other is hated, and they have both borne him children—both the beloved wife and the hated wife—if the firstborn son is of her that is hated,

¹⁶then on the day that the man causes his sons to inherit what he possesses, he may not make the son of the beloved wife the firstborn before the son of the hated wife, the son who is actually the firstborn.

¹⁷Instead, he must acknowledge the firstborn, the son of the hated wife, by giving him a double portion of all that he possesses; for that son is the beginning of his strength; the right of the firstborn belongs to him.