John Calvin Commentary Jeremiah 48:2

"The praise of Moab is no more; in Heshbon they have devised evil against her: Come, and let us cut her off from being a nation. Thou also, O Madmen, shalt be brought to silence: the sword shall pursue thee." — Jeremiah 48:2 (ASV)

The Prophet, as before, does not speak in an ordinary way but declares in lofty terms what God had committed to him, so that he might terrify the Moabites. It was not indeed that they heard his threats, but it was necessary for him to denounce vengeance in this vehement manner so that the Jews might know that the cruelty and pride of the Moabites, later mentioned, would not go unpunished.

Therefore he says, No more shall be the praise or the boasting of Moab over Heshbon. We may learn from this passage and from others that Heshbon had been taken from the Moabites, for it was occupied by God’s people because the Moabites had lost it, as Moses relates in Numbers 21:30 and Deuteronomy 2:26 and following.

But, as things change, when the Moabites became strong, they took this city away from the Israelites. Therefore the Prophet says that there would be no more boasting that they possessed Heshbon, for he adds, They have thought, or devised, etc. There is a striking allusion here, for Heshbon (from the Hebrew חשבון, chesbon) is derived from the root חשב, chesheb, meaning 'to devise' or 'to consult', as though Heshbon were a place of consultation or devising.

The Prophet then says that concerning Heshbon, they consulted against it (in Hebrew, חשבו עליה, cheshbu olie). He uses the root from which the name of the city is derived. Heshbon, then, previously called the place of consultation, was to have and find other counselors—namely, those who would contrive ruin for it.

Come ye; the Prophet here refers to the counsel taken by the Chaldeans: Come ye, and let us cut her off from being a nation. He then addresses another city: And thou, Madmen, shalt be cut off, for a sword shall go after thee, or pursue thee, as though the city itself were fleeing from the sword.

This is not because cities move from one place to another. Rather, when the citizens deliberate how they might drive away their enemies and resist their attacks—when they seek aid here and there, and when they employ their own remedies—they are said to flee. But the Prophet says, Thou shalt gain nothing by fleeing, for the sword shall pursue thee.