1 Samuel 17:55 in the World English Bible
When Saul saw David go out against the Philistine, he said to Abner, the captain of the army, “Abner, whose son is this youth?” Abner said, “As your soul lives, O king, I can’t tell.”
Context
54 And David took the head of the Philistine, and brought it to Jerusalem; but he put his armour in his tent.
55 And when Saul saw David go forth against the Philistine, he said unto Abner, the captain of the host, Abner, whose son is this youth? And Abner said, As thy soul liveth, O king, I cannot tell.
56 And the king said, Enquire thou whose son the stripling is.