The Lord told Saul that his kingdom is given to another because when he was given a task by the Lord, he failed his obligation (1 Samuel 1519). David, a devoted servant of the Lord and with no pretension, carried himself as wisely as a man could, and Saul feared David because of it.
In this is a lesson for us: people who reject the Lord fear (resist) others who serve him. This fear is the result of their own insecurity and apprehension. They think they know more than they do, and when exposed, they react adversely. Next time you oppose something or someone, be sure you understand what it is that you oppose. You know what it is that you believe and why it is that you believe it; now, do you know what it is that you oppose and why it is that you oppose it?
“Beloved, do not believe every spirit, but test the spirits to see whether they are from God, for many false prophets have gone out into the world” (1 John 4:1, ESV).
Note those who overreact to a situation. Their overreaction is the result of many things (I suppose), but the very least of which is the lack of knowledge and understanding about that toward which the response is made.