Jeremiah 34:8-10

The word which came to Jeremiah from the LORD after King Zedekiah had made a covenant with all the people who were in Jerusalem to proclaim release to them: that each man should set free his male servant and each man his female servant, a Hebrew man or a Hebrew woman; so that no one should keep them, a Jew his brother, in bondage. And all the officials and all the people obeyed who had entered into the covenant that each man should set free his male servant and each man his female servant, so that no one should keep them any longer in bondage; they obeyed, and set them free.