Revelation 21:24; And the Kings of the Earth Do Bring Their Glory and Honour into It
Revelation 21:24 (KJV) And the nations of them which are saved shall walk in the light of it: and the kings of the earth do bring their glory and honour into it.
What conditions prevail outside the New Jerusalem in parts of the new earth from which the nations and the kings come to the city is not a matter of revelation. One can only assume that in the absence of the curse that plagued the former earth (Revelation 22:3), condition will be vastly superior to the world of the present order.
Revelation 22:3 (KJV) And there shall be no more curse: but the throne of God and of the Lamb shall be in it; and his servants shall serve him:
Two features are certain: there will be no more sea (Revelation 21:1) and no more night (Revelation 21:25).
Revelation 21:1 (KJV) And I saw a new heaven and a new earth: for the first heaven and the first earth were passed away; and there was no more sea.
Revelation 21:25 (KJV) And the gates of it shall not be shut at all by day: for there shall be no night there.
“the kings of the earth do bring their glory and honour into it” as their earlier counterparts did to Babylon before the abolition of the old creation (Johnson). The present tense of “bring” marks this as habit and a matter of certainty in the new creation (Alford). Once again, a great metropolis will be the focus of the world and all lands will submit to her, but this time, under the exactly opposite moral conditions.
[Robert L. Thomas, Revelation 8-22 – An Exegetical Commentary, Moody, 1995, 478]