The lion-like sentry reported to his sovereign Lord that he was not neglecting his duty but was paying close attention to what he saw. He reported that a troop of riders in pairs had appeared and had announced the fall of Babylon (cf. Revelation 18:2). Her fallen idols symbolized their inability to protect her from her enemy (cf. Jeremiah 51:47; Jeremiah 51:52). Babylon fell several times: to the Assyrians in710 , 702 , 689 , and648 , and to the Medes and Persians in539 B.C, among others. The Medes were allies of the Babylonians in the earlier battles. But Babylon will fall again ( Revelation 16:19; Revelation 17-18). [source][source][source]