21:23 no need of the sun. Although the city will not need the light of the sun and moon, they will continue to exist forever (note Psalm 89:36; 148:3,6; Ecclesiastes 3:14), along with all the stars (e.g., Daniel 12:3).

21:24 kings of the earth. The identity of these “kings of the earth” and “the nations of them which are saved” is somewhat enigmatic at this time. There seem to be two possibilities. Assuming the new earth is the same size as the present earth, there will be extensive land areas outside the holy city (even the vast area occupied by the city would only cover about 1/75 of the earth’s surface, with none of the surface occupied by ocean waters). Consequently, in addition to their extensive “mansions” (John 14:2) in the holy city itself, each of the twenty billion or so inhabitants could have extensive “country estates” in the earth outside the city. It is noteworthy that there will still be a divine recognition of the “nations” that God had established. Even though there is only one race (i.e., the human race—Acts 17:26), there will always be nations. Another possibility is that all true believers among the earthly nations and kings will still be in their natural flesh, having been translated (like Enoch and Elijah) into the heavenly city before the holocaust and then returned to the new earth, finally to fill it and have godly dominion over it as God originally commanded Adam and Eve (Genesis 1:26-28). This would help explain the occasional Biblical references to “perpetual generations” (e.g., Genesis 9:12) and similar expressions (Genesis 22:17; Isaiah 9:7; Ephesians 3:21). Once the earth was “filled,” then future generations could be sent out to colonize other planets, and so on, forever. At this time, we simply don’t know.

21:25 no night there. Although there will be no “night” in the city itself, there will continue to be day and night in the cosmos as a whole (e.g., Revelation 20:10), as well as “months” on the new earth (Revelation 22:2).