Leviticus 25:43-45

⁴³You shall not oppress him with labor, and shall fear the Lord your God.

⁴⁴And whatever number of menservants and maidservants you shall have, you shall purchase male and female servants from the nations that are round about you.

⁴⁵And of the sons of the sojourners that are among you, of these you° shall buy and of their relations, all that shall be in your lands; let them be to you for a possession.