Jeremiah 34:8-10

The word which came to Jeremiah from the Lord, after King Zedekiah had made an agreement with all the people in Jerusalem, to give news in public that servants were to be made free; That every man was to let his Hebrew man-servant and his Hebrew servant-girl go free; so that no one might make use of a Jew, his countryman, as a servant: And this was done by all the rulers and the people who had taken part in the agreement, and every one let his man-servant and his servant-girl go free, not to be used as servants any longer; they did so, and let them go.