Leviticus 25:50-52

New Revised Standard Version, Anglicised

⁵⁰ They shall compute with the purchaser the total from the year when they sold themselves to the alien until the jubilee year; the price of the sale shall be applied to the number of years: the time they were with the owner shall be rated as the time of a hired labourer. ⁵¹ If many years remain, they shall pay for their redemption in proportion to the purchase price; ⁵² and if few years remain until the jubilee year, they shall compute thus: according to the years involved they shall make payment for their redemption.