John Gills Exposition of the Bible Commentary - Jeremiah 50:21
Go up against the land of Merathaim ,.... Thought to be the country of the Mardi, which lay part of it in Assyria, and part of it in Armenia; expressed in the dual number, because one part of it lay on one side the Tigris, and the other on the other side. Cyrus, with his army of Medes and Persians, is here called upon; who, according to Herodotus, passed through Assyria to Babylon: and so it may be agreeably rendered, "go by the land of Merathaim"; or the country of the Mardi. Many... read more
Matthew Henry's Complete Commentary - Jeremiah 50:21-32
Here, 1. The forces are mustered and commissioned to destroy Babylon, and every thing is got ready for a descent upon that potent kingdom: Go up against that land by Merathaim, the country of the Mardi, that lay part in Assyria and part in Armenia; and go among the inhabitants of Pekod, another country (mentioned Ezek. 23:23) which Cyrus took in his way to Babylon. The forces of Cyrus are called to go up against Babylon (Jer. 50:21), to come against her from the utmost border. Let all come... read more