In Philippians 2 the Apostle Paul challenges believers to be like minded with Christ who set the bar pretty high in terms of humility. Jesus himself taught and preached on humility. Our goal, just like Jesus and Paul, is to draw people to God and not attention to ourselves.
Goliath was the champion of the Philistines who intimated the army of Israel. (That’s the reason for talking about WWF wrestlers talking trash I just forgot the full analogy). David was an adolescent, little more than a child. Goliath came with a shield and a sword but David told him he came in the name of the Lord. That made all the difference.