2 Samuel 21:17

and smote Perhaps, and he (David) smote; as 2 Samuel 21:22 seems to imply that one of them fell by David's own hand.

that thou quench not the light of Israel Extinguishing the lamp is a natural metaphor for changing the light of prosperity into the darkness of calamity; and in particular David's sovereignty was the lamp which God's favour had lighted for the well-being of His people. An Arab in misfortune says, "Fate has put out my lamp." Cp. Job 18:6; Proverbs 13:9. The expression light of Israelseems to indicate that David was already king of all Israel, and if so, the incident may have happened in one of the wars recorded in ch. 2 Samuel 5:17-25.