Saul commanded his servants, [saying], Commune with David secretly, and say, Behold, the king has delight in you, and all his servants love you: now therefore be the king's son-in-law.
This chapter illustrates the fact that the godly often suffer through no fault of their own. It shows too that God causes even the worst intentions of the ungodly to strengthen the godly (cf. Psalms 7:12-16; Romans 8:28). We see here that the selfishness of the ungodly can produce irrational behavior (e.g., paranoia, 1 Samuel 18:12, and schizophrenia, 1 Samuel 18:11; 1 Samuel 18:17), and it leads to their ruin. I am not implying that this is the only cause of these mental problems. If we allow jealousy to take root in our hearts, it will devour us like a cancer. We should desire God’s glory, as Jonathan did, rather than our own glory, as Saul did.