Exodus 21:5

‘If a brother of yours becomes so poor with regard to you that he sells himself to you, you shall not subject him to a slave’s service.

“If your brother, a Hebrew man or woman, is sold to you, then he shall serve you six years, but in the seventh year you shall let him go to be free from you.

“And it will be that, if he says to you, ‘I will not go out from you,’ because he loves you and your household, since he fares well with you;

“I gave them My statutes and made them know My judgments, which, if a man does them, he will live by them.