There is no need for a sun means just that. In Creation, God made light before he created the sun and moon. Do not try to limit the New heaven by our human terms. This is going to be quite different from anything any of us knows!
The New Jerusalem, which is also called the Tabernacle of God, the Holy City, the City of God, the Celestial City, the City Foursquare, and Heavenly Jerusalem, is literally heaven on earth. It is referred to in the Bible in several places (Galatians 4:26; Hebrews 11:10; 12:22-24; and 13:14), but it is most fully described in Revelation 21.
In Revelation 21; the recorded history of man is at its end. All of the ages have come and gone. Christ has gathered His church in the Rapture (1 Thessalonians 4:15-17). The Tribulation has passed (Revelation 6-18). The battle of Armageddon has been fought and won by our Lord Jesus Christ (Revelation 19:17-21). Satan has been chained for the 1,000-year reign of Christ on earth (Revelation 20:1-3). A new, glorious temple has been established in Jerusalem (Ezekiel 40-48). The final rebellion against God has been quashed, and Satan has received his just punishment, an eternity in the lake of fire (Revelation 20:7-10.) The Great White Throne Judgment has taken place, and mankind has been judged (Revelation 20:11-15).
In Revelation 21:1 God does a complete make-over of heaven and earth (Isaiah 65:17; 2 Peter 3:12-13). The new heaven and new earth are what some call the “eternal state” and will be “where righteousness dwells” (2 Peter 3:13). After the re-creation, God reveals the New Jerusalem. John sees a glimpse of it in his vision: “The Holy City, the new Jerusalem, coming down out of heaven from God, prepared as a bride beautifully dressed for her husband” (Revelation 21:2). This is the city that Abraham looked for in faith (Hebrews 11:10). It is the place where God will dwell with His people forever (Revelation 21:3). Inhabitants of this celestial city will have all tears wiped away (Revelation 21:4).
The New Jerusalem will be fantastically huge. John records that the city is nearly 1,400 miles long, and it is as wide and as high as it is long-a perfect cube (Revelation 21:15-17). The city will also be dazzling in every way. It is lighted by the glory of God (verse 23). Its twelve foundations, bearing the names of the twelve apostles, are “decorated with every kind of precious stone” (verse 19). It has twelve gates, each a single pearl, bearing the names of the twelve tribes of Israel (verses 12 and 21). The street will be made of pure gold (verse 21).
The New Jerusalem will be a place of unimagined blessing. The curse of the old earth will be gone (Revelation 22:3). In the city are the tree of life “for the healing of the nations” and the river of life (verses 1-2). It is the place that Paul spoke of: “In the coming ages [God] might show the incomparable riches of his grace, expressed in his kindness to us in Christ Jesus” (Ephesians 2:6). The New Jerusalem is the ultimate fulfillment of all God’s promises. The New Jerusalem is God’s goodness made fully manifest.
Who are the residents of the New Jerusalem? The Father and the Lamb are there (Revelation 21:22). Angels are at the gates (verse 12). But the city will be filled with God’s redeemed children. The New Jerusalem is the righteous counter to the evil Babylon (Revelation 17), destroyed by God’s judgment (Revelation 18). The wicked had their city, and God has His. To which city do you belong? Babylon the Great or the New Jerusalem? If you believe that Jesus, the Son of God, died and rose again and have asked God to save you by His grace, then you are a citizen of the New Jerusalem. “God raised [you] up with Christ and seated [you] with him in the heavenly realms in Christ Jesus” (Ephesians 2:6). You have “an inheritance that can never perish, spoil or fade” (1 Peter 1:4). If you have not yet trusted Christ as your Savior, then we urge you to receive Him. The invitation is extended: “The Spirit and the bride say, ‘Come!’ And let the one who hears say, ‘Come!’ Let the one who is thirsty come; and let the one who wishes take the free gift of the water of life” (Revelation 22:17).