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.
David threw a stone with his shepherd’s sling, and it hit Goliath in the head and killed him. Then David took Goliath’s sword and cut off his head and brought it to Saul. As soon as he had gone to fight Goliath, Saul had forgotten who David was, so David had to remind him when he got back. Saul also forgot to give David money and a princess.
The moral of the story
Don’t bother giving people their promised compensation for risking their lives to help you. They won’t mind.