בָּ֣אוּ ׀ יְמֵ֣י הַפְּקֻדָּ֗ה בָּ֚אוּ יְמֵ֣י הַשִׁלֻּ֔ם יֵדְע֖וּ יִשְׂרָאֵ֑ל אֱוִ֣יל הַנָּבִ֗יא מְשֻׁגָּע֙ אִ֣ישׁ הָר֔וּחַ עַ֚ל רֹ֣ב עֲוֺנְךָ֔ וְרַבָּ֖ה מַשְׂטֵמָֽה׃
The days of visitation are come, The days of recompense are come, Israel shall know it. The prophet is a fool, the man of the spirit is mad! For the multitude of thine iniquity, the enmity is great.
Rashi on Hosea
the prophet shall be a fool Even some of their true prophets will be fools, e.g. Hananiah son of Azzur, who was originally a true prophet.