Leviticus 25:41

and then shall he depart from thee, both he and his children with him, and shall return unto his own family, and unto the possession of his fathers shall he return. This ordinance supplements Exodus 21:2, for it would come into effect both if the servant had not yet been with a master seven years, or if lie had declared his willingness to remain with his master and had received the mark of bondage in his ear.