Revelation 19:1 After this I heard what seemed to be the loud voice of a great multitude in heaven, crying out, “Hallelujah! Salvation and glory and power belong to our God, for his judgments are true and just; for he has judged the great prostitute who corrupted the earth with her immorality, and has avenged on her the blood of his servants.” Once more they cried out, “Hallelujah! The smoke from her goes up forever and ever.” And the twenty-four elders and the four living creatures fell down and worshiped God who was seated on the throne, saying, “Amen. Hallelujah!” And from the throne came a voice saying, “Praise our God, all you his servants, you who fear him, small and great.”
Those in heaven offer three reasons for their praise. First, “because His judgments are true and righteous.” Second, “because He has judged the notorious prostitute who corrupted the earth with her sexual immorality.” Third, because “He has avenged the blood of His slaves that was on her hands”. The vast multitude again sings, “Hallelujah! Her smoke ascends forever and ever!”.
We should not lose sight of the fact that the rejoicing multitude exults not merely in the defeat of God’s enemies – and theirs – but in the just and true nature of His judgments. The destruction of the great prostitute is a proper act of vengeance for her martyring the servants of God. This judgment, however, is only the beginning of the everlasting punishment of the wicked, as testified by the statement that her smoke “ascends forever and ever” (v. 3). “We do not rejoice at the sinfulness of Babylon,” writes Warren Wiersbe, “or even the greatness of Babylon’s fall. We rejoice that God is ‘true and righteous’ and that He is glorified by His holy judgments”
Phillips, Rob. The Searcher’s Guide to the Apocalypse: