15 And the Philistines had yet war again with Israel; and David went down, and his servants with him, and fought with the Philistines. And David was exhausted. 16 And Ishbibenob, who was of the children of Raphah—the weight of his lance was three hundred shekels of bronze, and he was girded with new [armour]—thought to smite David. 17 And Abishai the son of Zeruiah succoured him, and smote the Philistine and killed him. Then the men of David swore to him, saying, Thou shalt go no more out with us to battle, that thou quench not the lamp of Israel.
Matthew Henry's Commentary on 2 Samuel 21:15-17
Commentary on 2 Samuel 21:15-22
(Read 2 Samuel 21:15-22)
These events seem to have taken place towards the end of David's reign. David fainted, but he did not flee, and God sent help in the time of need. In spiritual conflicts, even strong saints sometimes wax faint; then Satan attacks them furiously; but those who stand their ground and resist him, shall be relieved and made more than conquerors. Death is a Christian's last enemy, and a son of Anak; but through Him that triumphed for us, believers shall be more than conquerors at last, even over that enemy.