Goliath disdained David because the lad had no battle scars; he was not a warrior at all but simply a fresh-faced boy (v. 42). Goliath assumed that he would win because his physical power and armaments were superior. As often, pride preceded his fall (Prov. 16:18).
Verses 45-47 give the clearest expression to David's faith in Yahweh. He viewed Yahweh as the commander of Israel's armies, a view of God that Saul never accepted but which made the difference between Saul's failure and David's success as the Lord's anointed (v. 45). He also saw God as the real deliverer of Israel (v. 46). Furthermore David was jealous for the reputation of God (v. 47), not his own glory, which so preoccupied Saul. His faith must have rested on God's promises concerning victory against the enemies of God's people for confidence in Himself and obedience to His word (Gen. 12:3; Deut. 31:1-8; Josh. 1:1-9).
"Intimidation. That's our MAJOR battle when we face giants. When they intimidate us, we get tongue-tied. Our thoughts get confused. We forget how to pray. We focus on the odds against us. We forget whom we represent, and we stand there with our knees knocking. I wonder what God must think, when all the while He has promised us, My power is available. There's no one on this earth greater. You trust Me.' . . .
"David lived by a very simple principle: nothing to prove, nothing to lose. He didn't try to impress anybody in the army of Israel. He didn't try to impress his brothers. He didn't even try to impress God. He just ran to meet Goliath."196