Event hough David was the youngest, God anointed him to be a king someday. Since then, the power of the Lord came upon him.
One day, Goliath, a giant Philistine attack the Israelite and David helped the King to fight against Goliath. He slung the stone and struck into Goliath's forehead. The stone sank into Goliath's forehead and he fell Goliath fell facedown on th
e grown.
David fought on the name of Lord the Almighty. And he won the fight.