1 Samuel 17:45-51 New King James Version (NKJV)
45 Then David said to the Philistine, “You come to me with a sword, with a spear, and with a javelin. But I come to you in the name of the Lord of hosts, the God of the armies of Israel, whom you have defied. 46 This day the Lord will deliver you into my hand, and I will strike you and take your head from you. And this day I will give the carcasses of the camp of the Philistines to the birds of the air and the wild beasts of the earth, that all the earth may know that there is a God in Israel. 47 Then all this assembly shall know that the Lord does not save with sword and spear; for the battle is the Lord’s, and He will give you into our hands.”
48 So it was, when the Philistine arose and came and drew near to meet David, that David hurried and ran toward the army to meet the Philistine. 49 Then David put his hand in his bag and took out a stone; and he slung it and struck the Philistine in his forehead, so that the stone sank into his forehead, and he fell on his face to the earth. 50 So David prevailed over the Philistine with a sling and a stone, and struck the Philistine and killed him. But there was no sword in the hand of David. 51 Therefore David ran and stood over the Philistine, took his sword and drew it out of its sheath and killed him, and cut off his head with it.
And when the Philistines saw that their champion was dead, they fled.
1 Samuel 17:45-51 New International Version (NIV)
45 David said to the Philistine, “You come against me with sword and spear and javelin, but I come against you in the name of the Lord Almighty, the God of the armies of Israel, whom you have defied. 46 This day the Lord will deliver you into my hands, and I’ll strike you down and cut off your head. This very day I will give the carcasses of the Philistine army to the birds and the wild animals, and the whole world will know that there is a God in Israel. 47 All those gathered here will know that it is not by sword or spear that the Lord saves; for the battle is the Lord’s, and he will give all of you into our hands.”
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.
50 So David triumphed over the Philistine with a sling and a stone; without a sword in his hand he struck down the Philistine and killed him.
51 David ran and stood over him. He took hold of the Philistine’s sword and drew it from the sheath. After he killed him, he cut off his head with the sword.
When the Philistines saw that their hero was dead, they turned and ran.