40 Then he took his staff in his hand and chose five smooth stones from the brook and put them in his shepherd's pouch. His sling was in his hand, and he approached the Philistine. 41 And the Philistine moved forward and came near to David, with his shield-bearer in front of him. 42 And when the Philistine looked and saw David, he disdained him, for he was but a youth, ruddy and handsome in appearance. 43 And the Philistine said to David, "Am I a dog, that you come to me with sticks?" And the Philistine cursed David by his gods. 44 The Philistine said to David, "Come to me, and I will give your flesh to the birds of the air and to the beasts of the field." 45 Then David said 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 the Lord of hosts, the God of the armies of Israel, whom you have defied. 46 This day the Lord will deliver you into my hand, and I will strike you down and cut off your head. And I will give the dead bodies of the host of the Philistines this day to the birds of the air and to the wild beasts 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 the Lord saves not with sword and spear. For the battle is the Lord's, and he will give you into our hand."
48 When the Philistine arose and came and drew near to meet David, David ran quickly toward the battle line to meet the Philistine. 49 And David put his hand in his bag and took out a stone and slung it and struck the Philistine on his forehead. The stone sank into his forehead, and he fell on his face to the ground. 50 So David prevailed over the Philistine with a sling and with a stone, and struck the Philistine and killed him. There was no sword in the hand of David. 51 Then David ran and stood over the Philistine and took his sword and drew it out of its sheath and killed him and cut off his head with it. When the Philistines saw that their champion was dead, they fled.
Matthew Henry's Commentary on 1 Samuel 17:40-51
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.
Commentary on 1 Samuel 17:48-58
(Read 1 Samuel 17:48-58)
See how frail and uncertain life is, even when a man thinks himself best fortified; how quickly, how easily, and by how small a matter, the passage may be opened for life to go out, and death to enter! Let not the strong man glory in his strength, nor the armed man in his armour. God resists the proud, and pours contempt on those who defy him and his people. No one ever hardened his heart against God and prospered. The history is recorded, that all may exert themselves for the honour of God, and the support of his cause, with bold and unshaken reliance on him. There is one conflict in which all the followers of the Lamb are, and must be engaged; one enemy, more formidable than Goliath, still challenges the armies of Israel. But "resist the devil, and he will flee from you." Go forth to battle with the faith of David, and the powers of darkness shall not stand against you. But how often is the Christian foiled through an evil heart of unbelief!