The battle between the Israelites and the Philistines did not stop for a long period of time. David's three brothers were in battle. Then one day, Jesse asked his youngest son David to bring food for his brothers. In the battlefield, he saw 'Goliath' called the giant of the Philistines yell at the Israelites and insult them.
"Idiots, Anyone can challenge me! Your god does not have the power to help you! Ha, Ha, Ha, All of you will die, until today, Nasty Cowards!"
Seeing his behavior, David said to the king.
"Your Majesty, he dares to insult the people of God. I cannot stand it. I will go to battle and fight against the Philistines."
Saul answered.
"You are too young to fight against them. "
David said to him.
"When I took care of my father's flock, I used to see lions or bears bite them off. But, I went after them, immediately and killed all them to rescue the flock. The Lord helped me rescue from roaring lions or bears. I believe that God will also rescue me out of the Philistines."
Saul can have no choice but to send David to the battle and make him fight against the enemies. Finally, he ordered David to do so. He clothed King's armor. The robe was too large and heavy for David to wear. So, he decided to go to the battle, with the armor off and his robe on.