Leviticus 25:48-52

48then he shall have redemption right after he has been sold. One of his brothers may redeem him,

49or his uncle, or his uncle’s son may redeem him, or one of his blood relatives from his family may redeem him; or 12if he prospers, he may redeem himself.

50He then, with his purchaser, shall calculate from the year when he sold himself to him up to the year of jubilee; and the price of his sale shall correspond to the number of years calculated. It is like the days of a hired worker that he will be with him.

51If there are still many years remaining, 3he shall refund part of his purchase price in proportion to them for his own redemption;

52but if few years remain until the year of jubilee, he shall so calculate with him. In proportion to his years he is to refund the amount for his redemption.