Jeremiah 34:15-16

So then you recently turned and repented, doing what was right in My sight, each man proclaiming release [from servitude] to his countryman [who was his bond servant]; and you had made a covenant before Me in the house which is called by My Name. Yet you backed out [of the covenant] and profaned My Name, and each man took back his servants, male and female, whom had been set free in accordance with their desire, and you brought them into servitude [again] to be your male servants and your female servants.” ’