John Calvin on Jeremiah 48:8

He confirms the previous verse; nor ought he to be deemed too wordy, for this prophecy was not announced, that it might cherish the hope and patience of the faithful only for a few days; but it was necessary for them to rest dependent for a long time on this promise, which God had given them many years before. This, then, is the reason why the Prophet confirms at large a truth in itself sufficiently clear. Come, he says, shall a waster to all the cities It now appears more clearly why he mentioned some of the cities, though, as we shall see, they were many, even that the Israelites might know that all the land of Moab was to be given up to desolation: Nor shall a city escape, for destroyed shall be the valley and the plain, as Jehovah has spoken It follows, —

Jeremiah 48:9

9. Give wings unto Moab, that it may flee and get away: for the cities thereof shall be desolate, without any to dwell therein.

9. Date alam ipsi Moab, quia volando volabit; et urbes ejus in vastationem erunt, ut non sit qui habitet in illis.