Israel’s miraculous defeat of the Syrian army (1 Kings 20:29) made it clear that God intended to eliminate the threat of a future attack from Ben-hadad. Ahab’s decision to form an alliance with the king of Syria may have been an attempt to accomplish God’s will in a different manner, but it did not guarantee that Ben-hadad would leave Israel alone.
While it is true that God is merciful, he judges those who choose to follow Satan. King Ahab was determined to maintain his secular lifestyle and was willing to align himself with one of Satan’s chief agents in order to do so. Ahab was more concerned with accumulating wealth than he was worshipping and serving God, so God punished him for his disobedience.
Even though he may not have been specifically instructed to kill Ben-hadad, it was obvious that God had delivered the king of Syria over to Ahab so that he could kill him. It was because Ben-hadad acknowledged his inferiority and subordination to Ahab by designating himself Ahab’s servant (1 Kings 20:32) that Ahab wanted to keep him alive. Ahab went so far as to refer to Ben-hadad as his brother, a sign that he intended to develop a close relationship with him.
After making a covenant with Ben-hadad, Ahab was visited by an unnamed prophet. “And he said unto him, Thus saith the LORD, Because thou hast let go out of thy hand a man whom I appointed to utter destruction, therefore thy life shall go for his life, and thy people for his people” (1 Kings 20:42). The Hebrew word translated appointed, cherem is derived from the word charam. “Charam is a religious word of great importance representing the devotion of some object to destruction or to a sacred use, not for the gratification of any selfish purpose” (2763).
Israel’s defeat of the Syrian army was meant to bring glory to God. Ahab could have sent a strong message to the surrounding nations by killing Ben-hadad. Instead, the covenant he formed with Ben-hadad let everyone know that Ahab’s relationship with Ben-hadad was more important to him than his relationship with God.