Whedon's Commentary on the Bible

1. Jehoshaphat had riches… and joined affinity with Ahab Probably his riches and honour begat in him “that bloated luxury which eats the core from manly virtue,” and in a thoughtless hour he proposed to ally the two kingdoms by the marriage of his son Jehoram with Athaliah, the daughter of Ahab and Jezebel. See note on 2 Kings 8:18. This alliance was the source of numerous woes to the kingdom of Judah, and is the darkest stain upon the otherwise fair fame of Jehoshaphat.

2. Ahab killed sheep and oxen for him Made for him a grand feast, thus seeking to secure his consent to assist him in the war with Syria. It was by such attention, and also by words of hope and promise, that Ahab persuaded Jehoshaphat to join him in the war.

3-34. The rest of this chapter is parallel with 1 Kings 22:4-39, where see notes.