The term Peter uses means to “have over,” to “hold above.” With this term Peter acknowledges that the creature known as the “king” (see this note for more on this) in fact has a position over, above other human creatures. The point of the term is not so much that there is no one over the king (in fact there is: the emperor) but is instead that he is above Peter’s readers (sojourners and exiles). Since the king is “above,” his readers need to “be subject.”