1 Samuel 17:50-58
English Standard Version
Chapter 17
50So David prevailed over the Philistine with a sling and with a stone, and struck the Philistine and killed him. There was no sword in the hand of David. 51Then David ran and stood over the Philistine and took his sword and drew it out of its sheath and killed him and cut off his head with it. When the Philistines saw that their champion was dead, they fled. 52And the men of Israel and Judah rose with a shout and pursued the Philistines as far as Gath and the gates of Ekron, so that the wounded Philistines fell on the way from Shaaraim as far as Gath and Ekron. 53And the people of Israel came back from chasing the Philistines, and they plundered their camp. 54And David took the head of the Philistine and brought it to Jerusalem, but he put his armor in his tent.
55As soon as Saul saw David go out against the Philistine, he said to Abner, the commander of the army, "Abner, whose son is this youth?" And Abner said, "As your soul lives, O king, I do not know."
56And the king said, "Inquire whose son the boy is."
57And as soon as David returned from the striking down of the Philistine, Abner took him, and brought him before Saul with the head of the Philistine in his hand.
58And Saul said to him, "Whose son are you, young man?" And David answered, "I am the son of your servant Jesse the Bethlehemite."