1 Samuel 17:31; 1 Samuel 17:55

31 What David said was overheard and reported to Saul, and Saul sent for him.
55 As Saul watched David going out to meet the Philistine, he said to Abner, commander of the army, "Abner, whose son is that young man?" Abner replied, "As surely as you live, O king, I don't know."