20 In his days Edom revolted from under the hand of Judah, and made a king over themselves. 21 Then Joram passed over to Zair, and all his chariots with him: and he rose up by night, and smote the Edomites that compassed him about, and the captains of the chariots; and the people fled to their tents. 22 So Edom revolted from under the hand of Judah unto this day. Then did Libnah revolt at the same time.
Matthew Henry's Commentary on 2 Kings 8:20-22
Commentary on 2 Kings 8:16-24
(Read 2 Kings 8:16-24)
A general idea is given of Jehoram's badness. His father, no doubt, had him taught the true knowledge of the Lord, but did ill to marry him to the daughter of Ahab; no good could come of union with an idolatrous family.