Shared ground

Revelation 15:3–4 presents worship as an interpretation of history: the singers praise God’s character and actions right before the next judgments unfold (Rev 15–16). The song links God’s earlier deliverance associated with Moses to the Lamb’s victory, presenting one continuous story of God rescuing and ruling.

The text explicitly praises God as “Lord God, the Almighty,” calls his works “great and marvelous,” and describes his ways as “righteous and true.” It also explicitly expands the horizon beyond one people by naming God “King of the nations” and by anticipating that “all the nations will come and worship.”

Where interpretation differs (only where needed)

One song or two. Some read “the song of Moses … and the song of the Lamb” as two distinct songs placed side by side. Others read it as one song with two anchors: Moses (Israel’s deliverance) and the Lamb (Christ’s victory). Either way, the point is that the worshipers interpret their rescue and God’s coming justice through the combined memory of Exodus-like deliverance and the Lamb’s triumph.

What “fear” means here. Some take “Who wouldn’t fear you?” to emphasize dread in the face of God’s overwhelming power and judgments. Others take it mainly as reverent awe and loyal acknowledgment. The wording allows both senses to overlap: the song grounds the response in God’s holiness and in the public revelation of his just actions.

How God’s “righteous acts” are revealed. Some connect this primarily to acts of deliverance (God vindicating his people). Others connect it primarily to acts of judgment (God exposing and answering evil). In the immediate context leading into the bowl judgments, the “revealing” naturally includes judgment, while the wider Exodus/Lamb framing keeps deliverance in view as well.

Why the disagreement exists The passage uses compressed worship language rather than detailed narrative explanation. Phrases like “song of Moses,” “fear,” and “righteous acts” draw on multiple biblical echoes and can point to more than one aspect of God’s action (rescue and judgment), especially in a book that repeatedly ties worship to unfolding crises.

What this passage clearly contributes It presents God’s coming climactic actions as morally grounded: his “ways” are not arbitrary but “righteous and true.” It also frames God’s reign as universal (“King of the nations”), aiming toward worldwide acknowledgment (“all the nations will come and worship”). Finally, it portrays worship as a reasoned response to what has become visible: God’s holiness and the disclosure of his just deeds, in continuity with both Moses and the Lamb (Revelation 15:3).