It is talking about the present Heaven, apparently, since the New Earth comes on the scene after the final judgment, and Revelation isn’t about the New Earth until Revelation 21-22. However, some aspects of the present Heaven may be shared by the future post-resurrection Heaven.
The Throne of the Ancient of Days: Daniel 7
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Randy Alcorn talks about the thrones of the Ancient of Days mentioned in Daniel's vision, and the significance of the throne for a Being that is without body. This video clip was excerpted from Randy's Eternity 101 DVD class.