1 Samuel 17:56
ESV
And the king said, "Inquire whose son the boy is."
NIV
The king said, "Find out whose son this young man is."
NASB
And the king said, 'You then, ask whose son the youth is.'
CSB
The king said, "Find out whose son this young man is!"
NLT
Well, find out who he is!' the king told him.
KJV
And the king said, Enquire thou whose son the stripling is.
NKJV
So the king said, “Inquire whose son this young man is.”
What does 1 Samuel 17:56 mean?
Saul has asked the commander of the army about David's family (1 Samuel 17:55). This conversation apparently takes place as David is approaching the field of battle to fight Goliath (1 Samuel 17:40). King Saul is impressed with young David's bravery and confidence in the Lord to give him victory. Nobody else had volunteered to fight the Philistine champion, including the king. Saul would also need to know who David's father was—to notify him of David's death or to reward his household by relieving them of paying taxes should David prove victorious (1 Samuel 17:25).Saul knew David, who both played the lyre for him and served as armor-bearer (1 Samuel 16:14–23; 17:15). Saul had also spoken with David this day (1 Samuel 17:31–40). But he apparently did not recall that David was the son of Jesse (1 Samuel 16:18; 17:12–15). Saul has asked the commander of his army, Abner, who David's father is (1 Samuel 17:55). Since Abner did not know, Saul now asks his commander to find out. The king will draft David into his permanent service, no longer allowing David to return home to Bethlehem to watch his father's sheep (1 Samuel 18:2).
First Samuel 17:55–58 depicts the meeting between King Saul and David immediately after David defeats the gigantic Philistine champion, Goliath. Saul has already met and employed David (1 Samuel 16:18–21); yet this victory has greatly increased the king's interest. Neither realize that this is the public beginning of a rivalry which will end in Saul's death and David's kingship. It will be God's judgment (1 Samuel 15:26), not any ambition from David (1 Samuel 24:9–11), which will bring down the jealous king (1 Samuel 18:7–9).
David, delivering food to his brothers at the Israelite army camp, hears the Philistine Goliath's defiant challenge. Single man combat could decide the battle, but no Israelite wanted to face the massive warrior. David is appalled that a Philistine would defy the armies of the living God. He volunteers to fight, and King Saul agrees. Before the battle, David declares that the Lord will give victory and thereby show the world that there is a God in Israel. David quickly kills and beheads Goliath. The Israelites chase the Philistines back to their own territory and plunder their camp. David brings Goliath's head to Saul.