Absalom and all the men of Israel said, “The advice of Hushai the Arkite is better than that of Ahithophel.” For the Lord had determined to frustrate the good advice of Ahithophel in order to bring disaster on Absalom.
From that day on, half of my men did the work, while the other half were equipped with spears, shields, bows and armor. The officers posted themselves behind all the people of Judah
It’s like a man going away: He leaves his house and puts his servants in charge, each with their assigned task, and tells the one at the door to keep watch.