David saw beyond the weapons, and size of Goliath. The philistines said, "here's our giant! Try to beat him!" And David said: "Here's my Giant, try to beat Him."
David knew that God was greater than Goliath and his weaponry.
We should have more of a simple child-like faith in God. It's easy to say that we trust Him, but how about when it comes down to you and your "giant"? Are you able to look beyond the sword and the spear and see God?