And he walked in the way of the king's of Israel, as did the house of Ahab,.... Imitated them in idolatry:
for the daughter of Ahab was his wife; whose name was Athaliah, 2 Kings 8:26, and by her he was drawn into idolatrous practices; of such bad consequence are marriages with idolaters; it is very much that so good a king as Jehoshaphat his father was should contract such an affinity; he suffered for it in more instances than one:
and he did evil in the sight of the Lord; was guilty of idolatry, than which nothing was more displeasing to the Lord; for he made high places, and compelled his subjects to commit idolatry, 2 Chronicles 21:11.