2 Kings 8:18

Of the kings of Israel. There are many indications that Judah was at this time closely allied to the nation of Israel and was walking in the ways of its northern neighbor. One indication is the inferred adoption of Israel’s method of chronological reckoning (see on ch. 9:29).

The daughter of Ahab. This was Athaliah (v. 26). The marriage of Athaliah, daughter of Ahab and Jezebel, to Jehoram, son of Jehoshaphat, served to seal an alliance between the two nations (2 Chron. 18:1). Such marriages between the reigning houses of nations that entered into alliance with each other were common in the ancient East. Judah gained for herself little but trouble by this marriage and alliance. Athaliah was a woman of the same stamp as her parents and was to bring to Judah much trouble before her death.

Under the alliance between the two nations Jehoshaphat joined forces with Ahab in Ahab’s war against Syria (1 Kings 22:4, 29; he joined with Ahab’s son Ahaziah in the making of ships at Ezion-geber (2 Chron. 20:35, 36), and joined Joram in war against Moab (2 Kings 3:7).

He did evil. This is the record that has thus far been given for the kings of Israel, but now Judah also was walking in the evil ways of its northern neighbor. When Jehoram came to the throne he slew all his brothers, to whom his father had given great treasures of silver and gold and fortified cities (2 Chron. 21:3, 4), and introduced gross forms of idolatry (2 Chron. 21:11).