When?
1 Now I saw a new heaven and a new earth, for the first heaven and the first earth had passed away. Also there was no more sea. 2 Then I, John, saw the holy city, New Jerusalem, coming down out of heaven from God, prepared as a bride adorned for her husband. 3 And I heard a loud voice from heaven saying, Behold, the tabernacle of God is with men, and He will dwell with them, and they shall be His people. God Himself will be with them and be their God. 4 And God will wipe away every tear from their eyes; there shall be no more death, nor sorrow, nor crying. There shall be no more pain, for the former things have passed away.
>> “When?” <<
Fifteen days after the last trump, which ends the Tribulation of the Saints, at Succot, is when the millennial reign begins.
The passage you posted from chapter 21 is after the end of the millennial reign, after the Earth and the universe has burned up with a loud noise. Then we will be tabernacling with the Father, in the place he prepared for us.
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