1 Samuel 17:40-50

Instead, he took his staff in his hand and chose five smooth stones from the wadi and put them in the pouch, in his shepherd’s bag. Then, with his sling in his hand, he approached the Philistine. The Philistine came closer and closer to David, with the shield-bearer in front of him. When the Philistine looked and saw David, he despised him because he was just a youth, healthy and handsome. He said to David, “Am I a dog that you come against me with sticks?” Then he cursed David by his gods. “Come here,” the Philistine called to David, “and I’ll give your flesh to the birds of the sky and the wild beasts!” David said to the Philistine, “You come against me with a sword, spear, and javelin, but I come against you in the name of the LORD of Armies, the God of the ranks of Israel — you have defied him. Today, the LORD will hand you over to me. Today, I’ll strike you down, remove your head, and give the corpses of the Philistine camp to the birds of the sky and the wild creatures of the earth. Then all the world will know that Israel has a God, and this whole assembly will know that it is not by sword or by spear that the LORD saves, for the battle is the LORD’s. He will hand you over to us.” When the Philistine started forward to attack him, David ran quickly to the battle line to meet the Philistine. David put his hand in the bag, took out a stone, slung it, and hit the Philistine on his forehead. The stone sank into his forehead, and he fell facedown to the ground. David defeated the Philistine with a sling and a stone. David overpowered the Philistine and killed him without having a sword.