1 Samuel 17:53

49 Then David reached into his bag, took out a stone, and slung it, striking the Philistine on the forehead. The stone sank into his forehead, and he fell facedown on the ground.

50 Thus David prevailed 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 grabbed the Philistine’s sword and pulled it from its sheath and killed him; and he cut off his head with the sword. When the Philistines saw that their hero was dead, they turned and ran.

52 Then the men of Israel and Judah charged forward with a shout and pursued the Philistines to the entrance of Gath and to the gates of Ekron. And the bodies of the Philistines were strewn along the Shaaraim road to Gath and Ekron.

53 When the Israelites returned from their pursuit of the Philistines, they plundered their camps.

54 David took the head of the Philistine and brought it to Jerusalem, and he put Goliath’s weapons in his own tent.

55 As Saul had watched David going out to confront the Philistine, he said to Abner the commander of the army, “Abner, whose son is this young man?” “As surely as you live, O king,” Abner replied, “I do not know.”

56 “Find out whose son this young man is!” said the king.

57 So when David returned from killing the Philistine, still holding his head in his hand, Abner took him and brought him before Saul.

Read all of 1 Samuel 17