“Looking back to the exodus from Egypt, Isaiah foresaw a future exodus from exile and showed Israel that God’s promise of deliverance entails his summons to separate from all that defiles. . . . The sky-high compost pillar of her sins has not escaped God’s notice, for he has ‘remembered her iniquities’ (Rev. 18:5; cf. 16:19). The new covenant promise that God will ‘remember no more’ the sins of his people assures us of both forgiveness and release from punishment (Jer. 31:34). By contrast, the assurance that God ‘remembers’ Babylon’s sins means that he holds her fully accountable, so that her punishment is inescapable.” (Dennis E. Johnson, Triumph of the Lamb, pp. 254–255).
Revelation 18 speaks of the might of the God who judges. That is true. But he is also a God who is mighty to save. Notice how many of the expressions used in describing judgment here in Revelation are used in the Old Testament as part of descriptions of God’s mercy. The sins of Babylon pile up the heavens—but Psalm 103 reminds you of God’s love for his people that is as high as the heavens are above the earth. The double is used in Isaiah 40 to emphasize God’s comforting mercy to his people. Whom does God command to come out? His people, echoing the language of Hosea. How can a God who is holy enough to punish cruel Babylon or Rome be merciful to you, a sinner? He cannot ignore your sin. He cannot simply turn off his holy wrath against it—for his holiness is part of his character. But what he can and did do was to send his Son into this world, so that you might escape from the judgment to come upon it. The wrath of God against your sin was borne by him. The only way to flee from God’s wrath is to flee to him in the person on his Son.
From the Reflection for Trinity Presbyterian Church of the OPC