The long warfare continued, and the progress of it is declared in the opening verse of this chapter: "And David waxed stronger and stronger, but the house of Saul waxed weaker and weaker."
At last matters in the kingdom of Israel were hastened to a crisis by a quarrel between Abner and Ishbosheth. The latter seems to have charged the former with a peculiar sin against his rights, a charge without foundation. This would explain Abner's fierce rejoinder. As a result of this he made overtures to David, during which he revealed his knowledge of God's purpose that David should occupy the throne. This is a revelation of the reason of his weakness. No man can hope successfully to bring any purpose to final issue when his own will power is weakened by an inward conviction that he is fighting against God.
Joab took advantage of this opportunity to wreak his vengeance on Abner by slaying him. David was at great pains to disavow all connection with the bloody act. His lamentation was the sincere regret of an upright man that anything should be done to aid an unjust cause.
the First Week after Epiphany