Passage
And the king said: Inquire thou, whose son this young man is.
And the king said: Inquire thou, whose son this young man is.
1 Samuel 17:54 And David taking the head of the Philistine, brought it to Jerusalem: but his armour he put in his tent.
1 Samuel 17:55 Now at the time that Saul saw David going out against the Philistines, he said to Abner, the captain of the army: Of what family is this young man descended, Abner? And Abner said: As thy soul liveth, O king, I know not.
1 Samuel 17:56 And the king said: Inquire thou, whose son this young man is.
1 Samuel 17:57 And when David was returned, after the Philistine was slain, Abner took him, and brought him in before Saul, with the head of the Philistine in his hand.
1 Samuel 17:58 And Saul said to him: Young man, of what family art thou? And David said: I am the son of thy servant Isai the Bethlehemite.
The verse centers on "king", "said", "inquire", "thou", "whose", and "young". It is saying that the verse draws attention to "king" and "said", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 55's "Now at the time that Saul saw..." into verse 57's "And when David was returned after the...", so "king" and "said" belong inside that flow. In 1 Samuel context, the local focus is covenant, worship, and faithfulness.
A plain takeaway is to answer the verse's own emphasis on "king" and "said" with trust shaped by these words, not by a vague optimism outside the passage.