20 And Benaiah the son of Jehoiada, a fighting man of Kabzeel, had done great acts; he put to death the two sons of Ariel of Moab: he went down into a hole and put a lion to death in time of snow: 21 And he made an attack on an Egyptian, a tall man: and the Egyptian had a spear in his hand; but he went down to him with a stick, and pulling the spear out of the hands of the Egyptian, put him to death with that same spear. 22 These were the acts of Benaiah, the son of Jehoiada, who had a great name among the thirty men of war. 23 He was honoured over the rest of the thirty, but he was not equal to the first three. And David put him over the fighting men who kept him safe.
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.