John Gill Commentary Jeremiah 48:42

"And Moab shall be destroyed from being a people, because he hath magnified himself against Jehovah." — Jeremiah 48:42 (ASV)

And Moab shall be destroyed from [being] a people
For some time, not always; since the captivity of Moab is promised to be returned, (Jeremiah 48:47); or from being such a people as they had been, enjoying so much ease, wealth, power, and prosperity. Abarbinel takes it to be a comparative, and renders it, "more than a people"; that is, shall be destroyed more than any other people; but the former sense is best; because he has magnified [himself] against the Lord;
the Targum is, against the people of the Lord; this is the cause of his destruction; (See Gill on Jeremiah 48:26).