As with other great ancient empires, Babylon’s ascendancy to wealth and glory was accompanied by moral decay, wickedness, and iniquity. Babylon’s corruption was so extensive that the very name became a symbol for worldliness, spiritual wickedness, and Satan’s kingdom.
God decreed that the Medes should completely destroy Babylon in its wickedness (see Isaiah 13:17–22). Under the rule of Cyrus the Great, an alliance of Medes and Persians dammed the mighty Euphrates River and marched through the riverbed and under the walls of Babylon to capture the city and overthrow the empire around 538 B.C. When Isaiah spoke of Babylon, he referred to both the actual empire as well as spiritual Babylon. Isaiah foresaw the graphic destruction of the Babylon of his day as a result of the great wickedness of its people. Consequently, he used the term Babylon in his prophecies to typify the spiritual condition of the latter days and the judgment that would come upon the world at the Second Coming of Jesus Christ (see D&C 1:16).
The Doctrine and Covenants clarifies Isaiah’s exhortation to “go ye forth of Babylon” (1 Nephi 20:20). Those who “bear the vessels of the Lord” must be clean, leaving the wickedness of the “spiritual Babylon” behind them (D&C 38:42; 133:5, 14).