Jamieson, Fausset and Brown on Jeremiah 5:15

15. (Jr 1:15; 6:22). Alluding to De 28:49, &c.

Israel--that is, Judah.

mighty--from an Arabic root, "enduring." The fourfold repetition of "nation" heightens the force.

ancient--The Chaldeans came originally from the Carduchian and Armenian mountains north of Mesopotamia, whence they immigrated into Babylonia; like all mountaineers, they were brave and hardy (see on Is 23:13).

language ... knowest not--Is 36:11 shows that Aramaic was not understood by the "multitude," but only by the educated classes [Maurer]. Henderson refers it to the original language of the Babylonians, which, he thinks, they brought with them from their native hills, akin to the Persic, not to the Aramaic, or any other Semitic tongue, the parent of the modern Kurd.