1 Samuel 17:55-58

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."