Because of the fall of Babylon (the prostitute, Revelation 17:5), these merchants respond like the kings of Revelation 18:9 did. John already used the word “weep” to describe the kings; he replaces the word “wail” (Revelation 18:9) with “mourn.” Just like the term “wail,” the latter term is characteristic of a funeral (Matthew 11:17; John 11:33). John had used the term in Revelation 18:7 in relation to Babylon’s boasting.
11 And the merchants of the earth weep and mourn for her, since no one buys their cargo anymore,