Ahithophel advised a quick surprise attack against David with a small force of 12,000 men (2 Samuel 17:1). This plan would give David no time to prepare or organize a defense.
David’s double agent, Hushai, gave different advice. He urged Absalom to wait and gather the entire army of Israel before attacking (2 Samuel 17:11). This plan promised a much larger force and would prevent David from using guerrilla tactics (small surprise attacks).
Because the Lord was working against Absalom, he rejected Ahithophel’s good advice and accepted Hushai’s poor advice (2 Samuel 17:14; compare 1 Kings 12:1–15).