Jamieson, Fausset and Brown on 1 Samuel 23:16-17

16-17. Jonathan went to David into the wood, and strengthened his hand in God--by the recollection of their mutual covenant. What a victory over natural feelings and lower considerations must the faith of Jonathan have won, before he could seek such an interview and give utterance to such sentiments! To talk with calm and assured confidence of himself and family being superseded by the man who was his friend by the bonds of a holy and solemn covenant, could only have been done by one who, superior to all views of worldly policy, looked at the course of things in the spirit and through the principles of that theocracy which acknowledged God as the only and supreme Sovereign of Israel. Neither history nor fiction depicts the movements of a friendship purer, nobler, and more self-denying than Jonathan's!

1Sa 23:19-29. Saul Pursues Him.