Revelation 11:15 just proclaimed 'the kingdom of the world has become our Lord's' — verse 17 directly responds with thanksgiving for His reign begun.

Revelation 1:4 uses the same divine self-designation 'who is and who was' — here the third element 'who is to come' is completed as His reign begins.

In Revelation 1:8, God declares 'who is and who was and who is to come' — the same divine title used here, now with the future aspect fulfilled.

In Revelation 4:8, the living creatures say 'who was, and is, and is to come' — the same eternal title, here adapted as God begins to reign.

In Revelation 4:9, the living creatures give glory and thanks to God on the throne, matching the elders' thanksgiving here.

In Revelation 15:3, the song of Moses and the Lamb thanks God Almighty for his deeds — a very similar hymn of thanksgiving for reign.

In Revelation 16:5, the same divine title 'who is and who was' appears in a judgment context — here His reign begins after judgment.

In Revelation 16:7, the altar affirms God Almighty's true judgments — another worship response acknowledging God's sovereign rule.

Revelation 19:6 echoes the same proclamation of God's reign — 'the Lord our God the Almighty reigns' — as here the elders give thanks for it.

Revelation 14:14 shows the Son of Man with a sickle, executing the judgment that follows God's assumption of power in 11:17.

Revelation 18:8 declares the Lord God mighty in judgment, illustrating the power the elders praise in 11:17.

Genesis 17:1 reveals God as 'God Almighty' (El Shaddai) — the same title used here for the sovereign Lord who begins to reign.

Psalm 98:1-3 celebrates God's salvation and reign with a new song — directly paralleling the elders' thanksgiving in Revelation 11:17 for God taking power and reigning.

Psalm 97:1 declares 'The LORD reigns', directly paralleling the elders' praise that God has begun to reign.

Psalm 99:1 proclaims 'The LORD reigns', reinforcing the same theme of divine sovereignty celebrated in Revelation.

1 Chronicles 29:12 acknowledges God's rule, strength, and power — directly echoed in Revelation 11:17 where God takes great power and begins to reign.