John Gill's Exposition of the Whole Bible
Jeremiah 20:4
For thus saith the, Lord, behold, I will make thee a terror to thyself, and to all thy friends,.... This is an interpretation of the name given, "Magormissabib": and shows that it was not a mere name he had, but that he should be in fact what that signifies; his conscience should be filled with terror at the judgments of God coming upon him for his sins; and which could not be concealed in his own breast from others, but he should be seized with such tremblings and shakings, and be such a spectacle of horror, that his own familiar friends, instead of delighting in his company, would shun it, and run away from him: unless this terror is to be understood of the Chaldean army, which should not only terrify him, but his friends, in whom he placed his confidence; these would be thrown into such a consternation, as not to be able to help him or themselves; to which the following words agree:
and they shall fall by the sword of their enemies, and thine eyes shall behold [it]; which would be an aggravation of the calamity, that not only he should be deprived of their assistance, but that they should fall into and by the hands of the Babylonians, and in his sight also:
and I will give all Judah into the hand of the king of Babylon; the whole land, and the inhabitants of it:
and he shall carry them captive into Babylon, and shall slay them with the sword; being in his hands, he shall do as he pleases with them, either carry them captive, or slay them; and some he will dispose of one way, and some another.