A.T. Robertson Commentary Revelation 18:10

"standing afar off for the fear of her torment, saying, Woe, woe, the great city, Babylon, the strong city! for in one hour is thy judgment come." — Revelation 18:10 (ASV)

Standing afar off (απο μακροθεν εστηκοτες). Perfect active (intransitive) participle of ιστημ. Vivid picture of the terrible scene, fascinated by the lurid blaze (cf. Nero's delight in the burning of Rome in A.D. 64), and yet afraid to draw near. On απο μακροθεν see Mr 5:6. There is a weird charm in a burning city. They feared the same fate (cf. verse 7 for βασανισμου, torment).

Woe, woe, the great city (ουαι, ουαι, η πολις η μεγαλη). Only example in the Apocalypse of the nominative with ουα except verses 16,19, though in Lu 6:25 and common in LXX (Isaiah 5:7,11, etc.). For the dative see Re 8:13, once so "strong" (η ισχυρα)!

In one hour (μια ωρα). Repeated in verses 16,19, and like μια ημερα (in one day) in verse 8. Some MSS. have here μιαν ωραν, like ποιαν ωραν (accusative of extent of time) in 3:3. See verse 8 (ο κρινας) for η κρισις σου (thy judgment). This is the dirge of the kings.