Deuteronomy 21:10-17

¹⁰If thou go out to fight against thy enemies, and the Lord thy God deliver them into thy hand, and thou lead them away captives,

¹¹And seest in the number of the captives a beautiful woman, and lovest her, and wilt have her to wife,

¹²Thou shalt bring her into thy house: and she shall shave her hair, and pare her nails,

¹³And shall put off the raiment, wherein she was taken: and shall remain in thy house, and mourn for her father and mother one month: and after that thou shalt go in unto her, and shalt sleep with her, and she shall be thy wife.

¹⁴Rut if afterwards she please thee not, thou shalt let her go free, but thou mayst not sell her for money nor oppress her by might because thou hast humbled her.

¹⁵If a man have two wives, one beloved, and the other hated, and they have had children by him, and the son of the hated be the firstborn,

¹⁶And he meaneth to divide his substance among his sons: he may not make the son of the beloved the firstborn, and prefer him before the son of the hated.

¹⁷But he shall acknowledge the son of the hated for the firstborn, and shall give him a double portion of all he hath: for this is the first of his children, and to him are due the first birthrights.