Leviticus 25:45-47

⁴⁵Moreover of the children of the strangers that sojourn among you, of them shall ye buy, and of their families that are with you, which they have begotten in your land: and they shall be your possession.

⁴⁶And ye shall make them an inheritance for your children after you, to hold for a possession; of them shall ye take your bondmen for ever: but over your brethren the children of Israel ye shall not rule, one over another, with rigor.

⁴⁷And if a stranger or sojourner with thee be waxed rich, and thy brother be waxed poor beside him, and sell himself unto the stranger or sojourner with thee, or to the stock of the stranger’s family;