John Gill Commentary 2 Chronicles 21:13

"but hast walked in the way of the kings of Israel, and hast made Judah and the inhabitants of Jerusalem to play the harlot, like as the house of Ahab did, and also hast slain thy brethren of thy father`s house, who were better than thyself:" — 2 Chronicles 21:13 (ASV)

And has walked in the way of the kings of Israel Worshipping the calves, and even Baal, with other idols, as they did: and has made Judah and the inhabitants of Jerusalem to go a whoring, like to the whoredoms of the house of Ahab; meaning spiritual whoredoms or idolatries: and has also slain your brethren of your father's house, which were better than yourself; more religious, more humane, more prudent, and fitter for government.