1 Samuel 17:45-50 KJV

43And the Philistine said unto David, Am I a dog, that thou comest to me with staves? And the Philistine cursed David by his gods.

44And the Philistine said to David, Come to me, and I will give thy flesh unto the fowls of the air, and to the beasts of the field.

45Then said David to the Philistine, Thou comest to me with a sword, and with a spear, and with a shield: but I come to thee in the name of the LORD of hosts, the God of the armies of Israel, whom thou hast defied.

46This day will the LORD deliver thee into mine hand; and I will smite thee, and take thine head from thee; and I will give the carcases of the host of the Philistines this day unto the fowls of the air, and to the wild beasts of the earth; that all the earth may know that there is a God in Israel.

47And all this assembly shall know that the LORD saveth not with sword and spear: for the battle is the LORD’s, and he will give you into our hands.

48And it came to pass, when the Philistine arose, and came, and drew nigh to meet David, that David hastened, and ran toward the army to meet the Philistine.

49And David put his hand in his bag, and took thence a stone, and slang it, and smote the Philistine in his forehead, that the stone sunk into his forehead; and he fell upon his face to the earth.

50So David prevailed over the Philistine with a sling and with a stone, and smote the Philistine, and slew him; but there was no sword in the hand of David.

51Therefore David ran, and stood upon the Philistine, and took his sword, and drew it out of the sheath thereof, and slew him, and cut off his head therewith. And when the Philistines saw their champion was dead, they fled.

52And the men of Israel and of Judah arose, and shouted, and pursued the Philistines, until thou come to the valley, and to the gates of Ekron. And the wounded of the Philistines fell down by the way to Shaaraim, even unto Gath, and unto Ekron.