45 Then said David to the Philistine, “You come to me with a sword, and with a spear, and with a javelin: but I come to you in the name of Yahweh of Armies, the God of the armies of Israel, whom you have defied. 46 Today, Yahweh will deliver you into my hand. I will strike you, and take your head from off you. I will give the dead bodies of the army of the Philistines this day to the birds of the sky, and to the wild animals of the earth; that all the earth may know that there is a God in Israel, 47 and that all this assembly may know that Yahweh doesn’t save with sword and spear: for the battle is Yahweh’s, and he will give you into our hand.”

Matthew Henry's Commentary on 1 Samuel 17:45-47

Commentary on 1 Samuel 17:40-47

(Read 1 Samuel 17:40-47)

The security and presumption of fools destroy them. Nothing can excel the humility, faith, and piety which appear in David's words. He expressed his assured expectation of success; he gloried in his mean appearance and arms, that the victory might be ascribed to the Lord alone.