John Gills Exposition of the Bible 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,... read more
Matthew Henry's Complete Commentary - 2 Samuel 21:1-9
Here I. Were are told of the injury which Saul had, long before this, done to the Gibeonites, which we had no account of in the history of his reign, nor should we have heard of it here but that it came now to be reckoned for. The Gibeonites were of the remnant of the Amorites (2 Sam. 21:2), who by a stratagem had made peace with Israel, and had the public faith pledged to them by Joshua for their safety. We had the story Josh. 9:1-27, where it was agreed (21-23) that they should have their... read more