John Calvin's Bible Commentary
Jeremiah 32:28
The import of the answer is, that though God would bring to an end the seventy years of exile, yet there was no reason for hypocrites to gather encouragement, for this promise did not belong to them. God then speaks here, in the first place, of his vengeance, in order to fill the despisers of his Law with dread, and to intimate that they were excluded from the favor of redemption, he afterwards adds, that he would at length be merciful to the exiles; but this favor is confined to the elect and faithful alone.
The two parts of the answer ought then to be noticed, for God seems here to set in opposition one to another two contrary things. But as I have said, in the former clause, he has in view the hypocrites, who applied to themselves, without faith and repentance, what the Prophet had testified of restoration. God then sets forth here his extreme severity, and then he mitigates that rigor; but he then turns his discourse to the elect, because they alone were capable of receiving his favor.
Let us now come to the words, I will deliver this city into the hand of the Chaldeans, and into the hand of King Nebuchadnezar, and he will take it this purpose was, that what Jeremiah himself had predicted by his command, should remain unalterable, that the city could not be delivered. For it might have disturbed the mind of the Prophet were the Jews shortly after to be delivered, and were the siege of the city to be raised: he might, in that case, have been exposed to ridicule, together with his prophecies, and rashness might have been objected to him, because he had dared to announce in God’s name what we before noticed. For this reason and purpose God declares that nothing could be changed, for the Chaldeans were to take the city; and thus he bids the Prophet to retain a quiet mind, and not to disturb himself, as though it was his intention to expose his prophecies to ridicule; for God’s sacred name would thus have been subjected to many reproaches. Had Jeremiah been proved guilty of falsehood, what would have been the consequence, but that the Jews would have insolently triumphed over God? God then declares again that the city was given over to destruction.