Goliath, a Philistine who was almost ten feet tall, challenged Israel to choose a man to fight him one-on-one. The losing nation would then become subject to the winning nation. David was told that King Saul would give great wealth and his daughter to the man who killed Goliath. So David told Saul he would fight Goliath.

Saul thought David was too young and inexperienced to do that, but David pointed out that as a shepherd, he had plenty of experience killing things. Saul let David try on his armor, but David (Saul’s armor-bearer) wasn’t used to bearing Saul’s armor. So he went to fight Goliath with no armor and no sword.