There was a great battle between Israel and the Philistines.
The Philistines had a great general - Goliath.
A man named Goliath, from the city of Gath, came out from the Philistine camp to challenge the Israelites. He was nearly three metres tall and wore bronze armour that weighed about 57 kilogrammes and a bronze helmet. His legs were also protected by bronze armour, and he carried a bronze javelin slung over his shoulder. His spear was as thick as the bar on a weaver's loom, and its iron head weighed about seven kilogrammes. A soldier walked in front of him carrying his shield.
This is the man David wanted to fight.
48 As the Philistine moved closer to attack him, David ran quickly toward the battle line to meet him. 49 Reaching into his bag and taking out a stone, he slung it and struck the Philistine on the forehead. The stone sank into his forehead, and he fell facedown on the ground.