20 In his days Edom revolted against the rule of Judah, and set up a king of their own. 21 Then Joram crossed over to Zair with all his chariots. He set out by night and attacked the Edomites and their chariot commanders who had surrounded him; but his army fled home. 22 So Edom has been in revolt against the rule of Judah to this day. Libnah also revolted 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.