Leviticus 25:53-55

⁵³As a hireling year by year shall he be with him; he shall not work him with rigour before thine eyes.

⁵⁴But if he be not redeemed within those years, he shall go out at the year of Jubilee, he and his children with him.

⁵⁵For the sons of Israel are My servants; they are servants whom I brought out of the land of Mizraim: I am the Lord your God.