Charles Ellicott Commentary 2 Chronicles 21:10

"So Edom revolted from under the hand of Judah unto this day: then did Libnah revolt at the same time from under his hand, because he had forsaken Jehovah, the God of his fathers." — 2 Chronicles 21:10 (ASV)

To this day. —See 2 Chronicles 5:9. The date thus assigned is some time prior to the captivity. No account is taken of Amaziah’s reduction of Edom (2 Chronicles 25:11–15), which was probably not permanent.

At the same time. —Literally, then revolted Libnah at that time. 2 Kings 8:22 ends here. The chronicler adds, from under his (that is, Jehoram’s) hand, and assigns a moral ground for the successful rebellion: For he had forsaken Jehovah, the God of his fathers.

(Thenius can hardly be right in asserting that the chronicler meant to say that Libnah, as a city of the priests, refused obedience to the idolatrous king; nor Hitzig, in explaining the revolt as merely a religious secession.) He forsook Jehovah by walking in the way of the kings of Israel, as did the house of Ahab, that is, by adopting and popularising the worship of the Tyrian Baal to please his wife and her people.

In those days, friendship with a foreign people seems to have involved recognition of their gods (Compare Amos 1:9 for the alliance between Tyre and Judah).

Libnah. —Syriac, the Edomites that lived in Libnah.