8 During Jehoram's reign, the Edomites revolted against Judah and crowned their own king. 9 So Jehoram went out with his full army and all his chariots. The Edomites surrounded him and his chariot commanders, but he went out at night and attacked them under cover of darkness. 10 Even so, Edom has been independent from Judah to this day. The town of Libnah also revolted about that same time. All this happened because Jehoram had abandoned the Lord, the God of his ancestors.
Matthew Henry's Commentary on 2 Chronicles 21:8-10
Commentary on 2 Chronicles 21:1-11
(Read 2 Chronicles 21:1-11)
Jehoram hated his brethren, and slew them, for the same reason that Cain hated Abel, and slew him, because their piety condemned his impiety. In the mystery of Providence such men sometimes prosper for a time; but the Lord has righteous purposes in permitting such events, part of which may now be made out, and the rest will be seen hereafter.