1 Samuel 18:1-4 CSB
When David had finished speaking with Saul, Jonathan was bound to David in close friendship, and loved him as much as he loved himself. Saul kept David with him from that day on and did not let him return to his father’s house.
Jonathan made a covenant with David because he loved him as much as himself. Then Jonathan removed the robe he was wearing and gave it to David, along with his military tunic, his sword, his bow, and his belt.
CSB: Christian Standard Bible