Why does it say that he went to war according to their counsel?
Malbim: He should have learned from his grandfather [Yehoshafat], who regretted that he went with Achav [Melech Yisrael] to fight Aram 1 . Also, after Aram struck Yehoram, Achazyahu should have rushed to return home. Rather, he was not concerned, and went to visit Yehoram in Yizre'el.
Yehoshafat, a Tzadik, regretted that he joined with a Rasha, like the Navi rebuked him (20:37). Achazyahu was a Rasha, like his brother-in-law Yehoram. Why should he not help him to fight against Nochrim?! (PF)
Who are "ha'Ramim?
Radak: They are ha'Aramim; the Aleph is omitted. The same applies to "mi'Beis ha'Surim Yatza" (Koheles 4:14).
