Jamieson, Fausset and Brown on 2 Samuel 18:24-32

24-32. David sat between the two gates--that is, in the tower-house on the wall that overhung the gate of Mahanaim. Near it was a watchtower, on which a sentinel was posted, as in times of war, to notify every occurrence. The delicacy of Ahimaaz' communication was made up by the unmistakable plainness of Cushi's. The death of Absalom was a heavy trial, and it is impossible not to sympathize with the outburst of feeling by which David showed that all thoughts of the victory he had won as a king were completely sunk in the painful loss he had sustained as a father. The extraordinary ardor and strength of his affection for this worthless son break out in the redundancy and vehemence of his mournful ejaculations.