Adam Clarke on Jeremiah 43:9

Take great stones - This discourse seems to have been delivered about a year after the destruction of Jerusalem. They pretended that they dared not stay in Judea for fear of the Chaldeans. The prophet here assures them that Nebuchadnezzar shall come to Egypt, extend his conquests in that kingdom, and place his tent over the very place where these stones were laid up, and destroy them. How these prophecies were fulfilled, see at the end of Jer 44:30 (note).