Leviticus 25:47-26:2

If a resident alien among you has prospered, and your kinsman being in straits, comes under his authority and gives himself over to the resident alien among you, or to an offshoot of an alien's family, he shall have the right of redemption even after he has given himself over. One of his kinsmen shall redeem him, or his uncle or his uncle's son shall redeem him, or anyone of his family who is of his own flesh shall redeem him; or, if he prospers, he may redeem himself. He shall compute with his purchaser the total from the year he gave himself over to him until the jubilee year; the price of his sale shall be applied to the number of years, as though it were for a term as a hired laborer under the other's authority. If many years remain, he shall pay back for his redemption in proportion to his purchase price; and if few years remain until the jubilee year, he shall so compute: he shall make payment for his redemption according to the years involved. He shall be under his authority as a laborer hired by the year; he shall not rule ruthlessly over him in your sight. If he has not been redeemed in any of those ways, he and his children with him shall go free in the jubilee year. For it is to Me that the Israelites are servants: they are My servants, whom I freed from the land of Egypt, I the Lord your God. You shall not make idols for yourselves, or set up for yourselves carved images or pillars, or place figured stones in your land to worship upon, for I the Lord am your God. You shall keep My sabbaths and venerate My sanctuary, Mine, the Lord's.