2 Samuel 21:7

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

2 Samuel 21:7 Meaning and Commentary

2 Samuel 21:7

But the king spared Mephibosheth, the son of Jonathan, the son
of Saul
As they did not name particular persons, only required seven sons, it was at the option of the king what sons to deliver to them, and therefore kept back Mephibosheth, who is thus described, to distinguish him from a son of Saul's of the same name, after mentioned:

because of the Lord's oath that [was] between them, between David and
Jonathan the son of Saul;
not merely or only out of affection to Mephibosheth, but because of the oath, that he might not be guilty of the same crime Saul was in slaying the Gibeonites.

2 Samuel 21:7 In-Context

5 And they answered the king, The man that consumed us and that devised against us, let us destroy him that nothing of him remains in any of the borders of Israel.
6 Let seven men of his sons be delivered unto us, and we will disjoint them, hanging them from a tree, unto the LORD in Gibeah of Saul, whom the LORD did choose. And the king said, I will give them.
7 But the king spared Mephibosheth, the son of Jonathan, the son of Saul, because of the LORD’s oath that was between them, between David and Jonathan the son of Saul.
8 But the king took the two sons of Rizpah, the daughter of Aiah, whom she gave birth unto Saul, Armoni and Mephibosheth, and five sons of Michal, the daughter of Saul, whom she had given birth unto Adriel, the son of Barzillai, the Meholathite;
9 and he delivered them into the hands of the Gibeonites, and they disjointed them hanging them from a tree in the hill before the LORD; and they fell all seven together and were put to death in the days of harvest, in the first days, in the beginning of barley harvest.
The Jubilee Bible (from the Scriptures of the Reformation), edited by Russell M. Stendal, Copyright © 2000, 2001, 2010