A.T. Robertson Commentary Revelation 19:2

"for true and righteous are his judgments; for he hath judged the great harlot, her that corrupted the earth with her fornication, and he hath avenged the blood of his servants at her hand." — Revelation 19:2 (ASV)

For (οτ). Because. The reason for God's judgments is given in 15:3; 16:7. The doom of Babylon seen in 14:7 is now realized.

For (οτ). Second use of οτ, explaining the first.

He hath judged (εκρινεν). First aorist (prophetic and climacteric, effective) active indicative of κρινω.

Which (ητις). The very one which.

Did corrupt (εφθειρεν). This is the terrible fact. First aorist active indicative of φθειρω. Cf. 11:18; 14:8; 17:2; 18:3.

And he hath avenged (κα εξεδικησεν). God has exacted vengeance for the blood of his servants from (εκ) her. Prophetic aorist again of εκδικεω with accusative and εκ with ablative as in 6:10.