Albert Barnes Commentary 2 Kings 8:16-19

"And in the fifth year of Joram the son of Ahab king of Israel, Jehoshaphat being then king of Judah, Jehoram the son of Jehoshaphat king of Judah began to reign. Thirty and two years old was he when he began to reign; and he reigned eight years in Jerusalem. And he walked in the way of the kings of Israel, as did the house of Ahab: for he had the daughter of Ahab to wife; and he did that which was evil in the sight of Jehovah. Howbeit Jehovah would not destroy Judah, for David his servant`s sake, as he promised him to give unto him a lamp for his children alway." — 2 Kings 8:16-19 (ASV)

This passage is parenthetical, resuming the history of the kingdom of Judah from 1 Kings 22:50.

The opening words of 2 Kings 8:16, “In the fifth year of Joram, son of Ahab, king of Israel, and of Jehoshaphat, king of Judah,” contradict all the other chronological records of Jehoshaphat (1 Kings 22:42; 1 Kings 22:51; 2 Kings 3:1; 2 Chronicles 20:31), which give him a reign of at least twenty-three years. For this reason, some have supposed that the words “Jehoshaphat being then king of Judah” were accidentally repeated. However, those who regard this verse and 2 Kings 1:17 as accurate suppose that Jehoshaphat gave his son the royal title in his sixteenth year, while advancing him to a real co-regency seven years later, in his twenty-third year. Two years after that, Jehoshaphat died, and Jehoram became the sole king.

In 2 Kings 8:17, the “eight years” of Jehoram’s reign are counted from his appointment as co-regent. His reign terminated in the twelfth year of Joram of Israel.

Regarding 2 Kings 8:18, Jehoshaphat’s political and social alliance with Ahab and his family had not been allowed to affect the purity of his own faith. However, his son Jehoram, influenced by his wife Athaliah (the daughter of Ahab), “walked in the way of the kings of Israel.” That is, he allowed the introduction of Baal worship into Judea.

Among Jehoram’s worst evil deeds was the cruel murder of his six brothers, whom he killed to obtain their wealth (2 Chronicles 21:4).

The natural consequence of Jehoram’s apostasy, as described in 2 Kings 8:19, would have been the destruction of his house and the transfer of Judah’s throne to another family. This would be comparable to the punishments of Jeroboam (1 Kings 14:10), Baasha (1 Kings 16:2–4), and Ahab (1 Kings 21:20–22). However, the promises God made to David prevented the removal of this dynasty. Instead, Jehoram was punished in other ways (2 Kings 8:22; 2 Chronicles 21:12–19).