1 Samuel 20:15-17
20:15 Don’t ever cut off your loyalty to my family, not even when the Lord has cut off every one of David’s enemies from the face of the earth
20:16 and called David’s enemies to account.” So Jonathan made a covenant with the house of David.
20:17 Jonathan once again took an oath with David, because he loved him. In fact Jonathan loved him as much as he did his own life.