Jeremias 34:14

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.

14 At the end of seven years ye shall let go every man his brother that is a Hebrew, that hath been sold unto thee, and hath served thee six years, thou shalt let him go free from thee: but your fathers hearkened not unto me, neither inclined their ear.