Revelation 21 sure seems to show the new earth and the new heaven coming together as God is then dwelling together with man in the new Jerusalem, and it descends from heaven onto the new earth. The separation is removed between them for the new earth and the new heaven, and that is forever and ever.
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, [
a]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.”
5 Then He who sat on the throne said, “Behold, I make all things new.” And He said [
b]to me, “Write, for these words are true and faithful.”
The Glory of the New Jerusalem
22 But I saw no temple in it, for the Lord God Almighty and the Lamb are its temple. 23 The city had no need of the sun or of the moon to shine [
l]in it, for the [
m]glory of God illuminated it. The Lamb
is its light. 24 And the nations [
n]of those who are saved shall walk in its light, and the kings of the earth bring their glory and honor [
o]into it. 25 Its gates shall not be shut at all by day (there shall be no night there). 26 And they shall bring the glory and the honor of the nations into [
p]it. 27 But there shall by no means enter it anything [
q]that defiles, or causes an abomination or a lie, but only those who are written in the Lamb’s Book of Life.