Leviticus 25:48 (KJV)

And ye shall take them as an inheritance for your children after you, to inherit them for a possession; they shall be your bondmen for ever: but over your brethren the children of Israel, ye shall not rule one over another with rigour.

And if a sojourner or stranger wax rich by thee, and thy brother that dwelleth by him wax poor, and sell himself unto the stranger or sojourner by thee, or to the stock of the stranger’s family:

After that he is sold he may be redeemed again; one of his brethren may redeem him:

Either his uncle, or his uncle’s son, may redeem him, or any that is nigh of kin unto him of his family may redeem him; or if he be able, he may redeem himself.

And he shall reckon with him that bought him from the year that he was sold to him unto the year of jubile: and the price of his sale shall be according unto the number of years, according to the time of an hired servant shall it be with him.