1)
What will Beis Yisrael not err about further?
1.
Malbim: They will not err about matters of Emunah.
2)
Whose Aveiros are discussed?
1.
Malbim: They sin via the false Nevi'im ? therefore I will punish them. This refers to Achav ben Kolayah [and Tzidkiyah ben Ma'aseah] ? Melech Bavel burned them, and they were "l'Os veli'Mshalim" (8).