Jeremiah 34:13-16

13“This is what the Lord, the God of Israel, says: I made a covenant with your ancestors when I brought them out of Egypt, out of the land of slavery. I said, 14‘Every seventh year each of you must free any fellow Hebrews who have sold themselves to you. After they have served you six years, you must let them go free.’ Your ancestors, however, did not listen to me or pay attention to me. 15Recently you repented and did what is right in my sight: Each of you proclaimed freedom to your own people. You even made a covenant before me in the house that bears my Name. 16But now you have turned around and profaned my name; each of you has taken back the male and female slaves you had set free to go where they wished. You have forced them to become your slaves again.