2 Samuel 1:23-25 — Saul and Jonathan were lovely and pleasant in their lives, and in their death they were not divided: they were swifter than eagles, they were stronger than lions. Ye daughters of Israel, weep over Saul, who clothed you in scarlet, with other delights, who put on ornaments of gold upon your apparel. How are the mighty fallen in the midst of the battle! O Jonathan, thou wast slain in thine high places. 
One of the saddest, and most noble, stories in the Bible is the tragic death of Saul and Jonathan. You remember it, I’m sure. Saul was the first king of Israel, but was rejected by God. David was God’s chosen replacement. As Saul, provoked by demons, deteriorated, he attacked David who fled for his life.
David and Saul’s son Jonathan were the closest of friends — Jonathan incurred the wrath of his father by defending David to him. Saul even tried to kill him … and yet … Jonathan would not leave him.

Jonathan was loyal to his friend, and loyal to his father too.

David was loyal as well. You might thing he had plenty of reason to resent Saul  — but he would not lift his hand against him, not even to save his own life. His loyalty to Saul would not allow it nor would his higher loyalty to God. When he had the chance he said “The Lord forbid that I should stretch forth mine hand against the Lord’s anointed” (1 Samuel 26:11).

In this fatal triangle there was one who wasn’t loyal. Saul, driven mad with jealousy and rage, could not see David as the faithful servant that he was. He tried, instead, to hunt him down and kill him.

Jonathan could have gone with David — but he didn’t. He stayed, despite everything, with his father. 

The triangle of divided loyalties inevitably weakened Israel. David, Saul’s best general, was not fighting with him but instead was living the life of a mercenary warlord. That weakness allowed the Philistines to attack Israel more or less as they wished.

The Philistines attack and Israel, fatally weakened, are roundly defeated. Saul and Jonathan die.

David is devastated by the deaths of Saul and Jonathan. Even at this moment he is loyal to Saul and to Jonathan, mourning their deaths. He doesn’t rejoice that the way is open for the Lord’s promise of the Kingship to be fulfilled.

Jonathan is caught between two loyalties and destruction inevitably follows. It is always so. Jesus said it in Another context … You cannot serve two masters …