1 Samuel 17:54-55

17:54 David took the head of the Philistine and brought it to Jerusalem, and he put Goliath’s weapons in his tent.

17:55 Now as Saul watched David going out to fight the Philistine, he asked Abner, the general in command of the army, “Whose son is this young man, Abner?” Abner replied, “As surely as you live, O king, I don’t know.”