Jeremiah 34:14

“If you buy a Hebrew slave, he shall serve for six years; but on the seventh he shall go out as a free man without payment.

“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.

The word which came to Jeremiah from Yahweh after King Zedekiah had cut a covenant with all the people who were in Jerusalem to proclaim release to them:

“Also I have sent to you all My slaves the prophets, rising up early and sending, saying: ‘Turn now every man from his evil way and make good your deeds, and do not walk after other gods to serve them. Then you will inhabit the land which I have given to you and to your fathers; but you have not inclined your ear or listened to Me.