Albert Barnes Commentary 2 Samuel 17

This night - This refers to the night of the day on which David fled and Absalom entered Jerusalem. Ahithophel’s strategy was to fall upon David by surprise and, in the initial confusion of the surprised army, to seize and kill only David.

The man whom you seek—namely, David. Ahithophel means to say, "If I can only strike down David, there will be no civil war; all the people will peaceably submit."

At this time - Rather, “The counsel that Ahithophel has given this time is not good.” He contrasts it with the counsel given before (2 Samuel 16:21), which was good. This gave his conduct an appearance of candor, and thus added weight to his dissent. Observe the effect of David’s prayer in 2 Samuel 15:31.

Some pit, or in some other place - The Hebrew text reads “in one of the pits,” or “in one of the places.” Therefore, the word “place” must have a specific, defined meaning. It is probably used here, as it is elsewhere, to mean a “dwelling-house” or “village.” In that district, these might have been fortified houses (2 Samuel 17:12; 1 Samuel 26:25).

Hushai’s argument was that there was no chance of seizing David by surprise, as Ahithophel had suggested. Sharp fighting was certain to occur, and the terror inspired by the names of David, Joab, Abishai, Ittai, and their companions would magnify the first few blows into a perceived victory, causing Absalom’s men to flee in a panic. It is likely that Absalom was not a courageous man; knowing this, Hushai skillfully magnified the terror of the military prowess of David and his mighty men.

As the dew — Like the drops of dew, this refers to the vast number of our army and our irresistible and unavoidable descent upon our enemies.