John Calvin Commentary Jeremiah 4:9

"And it shall come to pass at that day, saith Jehovah, that the heart of the king shall perish, and the heart of the princes; and the priests shall be astonished, and the prophets shall wonder." — Jeremiah 4:9 (ASV)

Although their power was greatly diminished, the royal dignity still continued with the Jews. Relying on this distinction, they hoped for sufficient protection. Therefore, they were not moved by any denunciation, because the royal power—though not entirely secure, yet still existing to some degree—was like a shield to them.

We also know what pride filled the courtiers, for they extolled their kings and thus made a show of their kings' prudence and magnanimity. Therefore, since this foolish notion of the chief men concerning their king, and their delusive boasting, deceived the Jews, the Prophet says, In that day perish shall the heart of the king, and the heart of the princes.

By heart, he undoubtedly means the understanding or the mind, as the word is often understood in many other places. Moses says, God has not yet given you a heart to understand (Deuteronomy 29:4). The Latins also call men “hearted” (cordatos) who excel in intelligence and wisdom.

So, then, the Prophet shows that it was a vain and deceptive fancy for the people to expect that the king would be an invincible defense to them. For, he says, “The king shall then be deprived of understanding and reason; and the counselors, who claim to have understanding, shall then be found to be entirely foolish. Therefore, there is no basis for that vain confidence which deceives you.” The Prophet briefly intended to shake off that false confidence by which the Jews were intoxicated, when they thought that there was certain safety in the intelligence of the king and princes.

He says the same thing concerning the priests as well as the prophets, since much glory belonged to the priestly order; for the tribe of Levi had not taken that honor upon itself, but God himself had appointed priests over the people. Consequently, an opinion prevailed that the priests could not be without understanding and wisdom.

With regard to the prophets, Jeremiah undoubtedly conceded the name 'prophet' to impostors who falsely used the name of God; this manner of speaking is common in the writings of the prophets. He does not, then, mean those true and faithful ministers of God who properly carried out their office, but those who boasted of the name and title. And he says of these that they would be astonished.

In short, he deprives the people of that false confidence by which they hardened themselves, so that they did not fear God’s judgment.

But this passage deserves special notice because it shows that God’s grace is not tied either to ranks of men or to titles. The prophetic office had always been highly respected, nor was the priestly office without honor, for it was established by God’s command. But Jeremiah nevertheless declares that there would be no understanding in the priests and in the prophets, because they would become stupefied and astonished.

And with regard to the king, we know that he was the representative of Christ; yet Jeremiah pronounces the same thing concerning the king and also his counselors: that they would be made blind by the just vengeance of God, so that they would not see anything. He afterward adds—