20 There was also Benaiah son of Jehoiada, a valiant warrior from Kabzeel. He did many heroic deeds, which included killing two champions of Moab. Another time, on a snowy day, he chased a lion down into a pit and killed it. 21 Once, armed only with a club, he killed an imposing Egyptian warrior who was armed with a spear. Benaiah wrenched the spear from the Egyptian's hand and killed him with it. 22 Deeds like these made Benaiah as famous as the Three mightiest warriors. 23 He was more honored than the other members of the Thirty, though he was not one of the Three. And David made him captain of his bodyguard.
Matthew Henry's Commentary on 2 Samuel 23:20-23
Commentary on 2 Samuel 23:8-39
(Read 2 Samuel 23:8-39)
David once earnestly longed for the water at the well of Bethlehem. It seems to be an instance of weakness. He was thirsty; with the water of that well he had often refreshed himself when a youth, and it was without due thought that he desired it. Were his valiant men so forward to expose themselves, upon the least hint of their prince's mind, and so eager to please him, and shall not we long to approve ourselves to our Lord Jesus, by ready compliance with his will, as shown us by his word, Spirit, and providence? But David poured out the water as a drink-offering to the Lord. Thus he would cross his own foolish fancy, and punish himself for indulging it, and show that he had sober thoughts to correct his rash ones, and knew how to deny himself. Did David look upon that water as very precious which was got at the hazard of these men's blood, and shall not we much more value those benefits for purchasing which our blessed Saviour shed his blood? Let all beware of neglecting so great salvation.