1 Samuel 18:3

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

1 Samuel 20:8-17

Therefore deal kindly with thy servant, for thou have brought thy servant into a covenant of LORD with thee. But if there be in me iniquity, kill me thyself, for why should thou bring me to thy father?

1 Samuel 20:42

And Jonathan said to David, Go in peace, inasmuch as we have sworn both of us in the name of LORD, saying, LORD shall be between me and thee, and between my seed and thy seed, forever. And he arose and departed, and Jonathan went i

1 Samuel 23:18

And those two made a covenant before LORD. And David abode in the forest, and Jonathan went to his house.

2 Samuel 9:1-3

And David said, Is there yet any who is 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 LORD's oath that was between them, between David and Jonathan the son of Saul.

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 rose up, and Phicol the captain of his army, and they returned into the land of the Philistines.
1 Samuel 23:18
And those two made a covenant before LORD. And David abode in the forest, and Jonathan went to his house.
Proverbs 17:17
A friend loves at all times, and a brother is born for adversity.