Commentaries:
Jamieson, Fausset, and Brown
the mountains—namely, which separate Media and Assyria, and on one of which the banner to rally the hosts is supposed to be reared.
tumultuous noise—The Babylonians are vividly depicted as hearing some unwonted sound like the din of a host; they try to distinguish the sounds, but can only perceive a tumultuous noise.
nations—Medes, Persians, and Armenians composed Cyrus' army.
Other Jamieson, Fausset, and Brown entries containing Isaiah 13:4:
Jeremiah 11:16
Ezekiel 1:24
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