The chapter is about the Millennial reign, where there will still be some mortals, not the New Jerusalem.
Sorry, that appears to be a distinction without a difference. Once again, Isaiah 60:21 states, “Then all your people will be righteous and they will possess the land forever. They are the shoot I have planted, the work of my hands, for the display of my splendor.”
Notice the phrase ‘they will possess the land forever’. It makes no difference whether it’s the Millennial reign or post-Millennial period, the word forever clearly implies extending beyond the coming Millennium, so the righteous humans will continue to reside on planet earth.
As I already said, the chapter mixes two periods, and one needs to read the last chapters of the Revelation, where there is a great amount of specificity and detail that contradicts your theory.
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