In ancient Rome, the word hand ("manus") referred to legal control / authority. So if a woman married into the "hand" of her husband, she was under his legal control. If she remained under her father's legal control, it was a different kind of manus, and she had the right to divorce her husband and return to her father's household, with her dowry intact (owed to her father). If her father died he could leave her to herself in his will, and she would then be "out of hand" -- i.e., under her own hand, or her own legal control. It was called suae iuris, to her own law or to her own right. This came into common practice around the turn of the first century (from BC to AD). I don't think the term "out of hand" goes back that far, though.