40 And he took his staff in his hand, and chose him five smooth stones out of the brook, and put them in the shepherd's bag which he had, even in his wallet; and his sling was in his hand: and he drew near to the Philistine. 41 And the Philistine came on and drew near unto David; and the man that bare the shield went before him. 42 And when the Philistine looked about, and saw David, he disdained him; for he was but a youth, and ruddy, and withal of a fair countenance. 43 And the Philistine said unto David, Am I a dog, that thou comest to me with staves? And the Philistine cursed David by his gods.

Matthew Henry's Commentary on 1 Samuel 17:40-43

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.