Deuteronomy 21:14-16

New Century Version

¹⁴ But if you are not pleased with her, you must let her go anywhere she wants. You must not sell her for money or make her a slave, because you have taken away her honor.

The Oldest Son

¹⁵ A man might have two wives, one he loves and one he doesn’t. Both wives might have sons by him. If the older son belongs to the wife he does not love, ¹⁶ when that man wills his property to his sons he must not give the son of the wife he loves what belongs to the older son, the son of the wife he does not love.