Genesis 31:49-53

49But it was also called Mizpah (which means “watchtower”), for Laban said, “May the Lord keep watch between us to make sure that we keep this covenant when we are out of each other’s sight.

50If you mistreat my daughters or if you marry other wives, God will see it even if no one else does. He is a witness to this covenant between us.

51“See this pile of stones,” Laban continued, “and see this monument I have set between us.

52They stand between us as witnesses of our vows. I will never pass this pile of stones to harm you, and you must never pass these stones or this monument to harm me.

53I call on the God of our ancestors—the God of your grandfather Abraham and the God of my grandfather Nahor—to serve as a judge between us.” So Jacob took an oath before the fearsome God of his father, Isaac, to respect the boundary line.