5 Whatever Saul gave David to do, he did it - and did it well. So well that Saul put him in charge of his military operations. Everybody, both the people in general and Saul's servants, approved of and admired David's leadership.
6 As they returned home, after David had killed the Philistine, the women poured out of all the villages of Israel singing and dancing, welcoming King Saul with tambourines, festive songs, and lutes. 7 In playful frolic the women sang, Saul kills by the thousand, David by the ten thousand! 8 This made Saul angry - very angry. He took it as a personal insult. He said, "They credit David with 'ten thousands' and me with only 'thousands.' Before you know it they'll be giving him the kingdom!" 9 From that moment on, Saul kept his eye on David.
Matthew Henry's Commentary on 1 Samuel 18:5-9
Commentary on 1 Samuel 18:1-5
(Read 1 Samuel 18:1-5)
The friendship of David and Jonathan was the effect of Divine grace, which produces in true believers one heart and one soul, and causes them to love each other. This union of souls is from partaking in the Spirit of Christ. Where God unites hearts, carnal matters are too weak to separate them. Those who love Christ as their own souls, will be willing to join themselves to him in an everlasting covenant. It was certainly a great proof of the power of God's grace in David, that he was able to bear all this respect and honour, without being lifted up above measure.
Commentary on 1 Samuel 18:6-11
(Read 1 Samuel 18:6-11)
David's troubles not only immediately follow his triumphs, but arise from them; such is the vanity of that which seems greatest in this world. It is a sign that the Spirit of God is departed from men, if, like Saul, they are peevish, envious, suspicious, and ill-natured. Compare David, with his harp in his hand, aiming to serve Saul, and Saul, with his javelin in his hand, aiming to slay David; and observe the sweetness and usefulness of God's persecuted people, and the barbarity of their persecutors. But David's safety must be ascribed to God's providence.