Jeremiah 34:9 in the King James Version
That every man should let his manservant, and every man his maidservant, being an Hebrew or an Hebrewess, go free; that none should serve himself of them, to wit, of a Jew his brother.
Context
8 The word came to Jeremiah from the LORD, after King Zedekiah had made a covenant with all the people who were at Jerusalem, to proclaim liberty to them,
9 that every man should let his male servant, and every man his female servant, who is a Hebrew or a Hebrewess, go free, that no one should make bondservants of them, of a Jew his brother.
10 All the princes and all the people obeyed who had entered into the covenant, that everyone should let his male servant and everyone his female servant go free, that no one should make bondservants of them any more. They obeyed and let them go,