1 Samuel 23:16-18

16And Saul’s son Jonathan went to David at Horesh and helped him find strength in God. 17“Don’t be afraid,” he said. “My father Saul will not lay a hand on you. You will be king over Israel, and I will be second to you. Even my father Saul knows this.”

18The two of them made a covenant before the LORD . Then Jonathan went home, but David remained at Horesh.