1 Samuel 18:3

Then Jonathan made a covenant with David because he loved him as himself.

1 Samuel 20:8-17

"Therefore deal kindly with your servant, for you have brought your servant into a covenant of the LORD with you But if there is iniquity in me, put me to death yourself; for why then should you bring me to your father?"

1 Samuel 20:42

Jonathan said to David, "Go in safety, inasmuch as we have sworn to each other in the name of the LORD, saying, 'The LORD will be between me and you, and between my descendants and your descendants forever.'" Then he rose and departed, while Jonathan went into the city.

1 Samuel 23:18

So the two of them made a covenant before the LORD; and David stayed at Horesh while Jonathan went to his house.

2 Samuel 9:1-3

Then David said, "Is there yet anyone left of the house of Saul, that I may show him kindness for Jonathan's sake?"

2 Samuel 21:7

But the king spared Mephibosheth, the son of Jonathan the son of Saul, because of the oath of the LORD which was between them, between David and Saul's son Jonathan.

Treasury of Scripture Knowledge

Summary

Then Jonathan and David made a covenant, because he loved him as his own soul.

Bible References

General references

Genesis 21:32
So they made a covenant at Beersheba; and Abimelech and Phicol, the commander of his army, arose and returned to the land of the Philistines.
1 Samuel 23:18
So the two of them made a covenant before the LORD; and David stayed at Horesh while Jonathan went to his house.
Proverbs 17:17
A friend loves at all times, And a brother is born for adversity.