John Calvin Commentary Jeremiah 50:46

"At the noise of the taking of Babylon the earth trembleth, and the cry is heard among the nations." — Jeremiah 50:46 (ASV)

This is to anticipate an objection; for many might have said, “How can it be that Babylon should fall in this way, on whose monarchy so many and such extensive countries depend?” Since, then, such an event, appearing so unreasonable, might occur to them, the Prophet addresses the objection and answers in advance that though the earth shook, yet this would surely take place. He shows, at the same time, how great the calamity would be, for by its noise it would make the whole world tremble: thus it would be better known how grievous God’s vengeance on the Babylonians was to be; for it was not to happen without the shaking of the whole earth.