The New Jerusalem cannot be a physical city, as commonly believed by Christians, for the following reasons:
First, the New Jerusalem is the crystallized product of God’s work in the old creation throughout the generations. If this crystallized product is merely a physical city, it would seem to be too low and would not have any spiritual value.
Second, the New Jerusalem is the consummation of the entire divine revelation in the Bible. If it is merely a physical city, it would make the divine revelation of mystery not so mysterious after all.
Third, the revelation of the entire book of Revelation is mainly made known to us by signs (Rev. 1:1) symbolizing the important persons and things, such as the golden lampstands in 1:12, signifying the churches bearing the shining testimony of Jesus Christ; the stars in 1:16, signifying the bright and shining messengers of the churches; the mysterious Babylon the Great in 17:5, signifying the religious Rome; and the bride in 19:7, signifying the overcoming saints as the spouse of Christ. Hence, the New Jerusalem also should be a sign signifying the dwelling place of God and man in eternity.
After God finished the creation of all things and man, He used different ways in the different dispensations in the old heaven and old earth to carry out His work in the man of the old creation by choosing, redeeming, renewing, transforming, and glorifying them; thus, He perfects them according to His desire and builds them up to be His eternal habitation, which is the New Jerusalem of His heart’s desire. This is the crystallized product and masterpiece of God’s work of the new creation throughout the generations.
The New Jerusalem is a composition of all the redeemed and perfected saints in both the Old and New Testaments throughout the generations.
The names of the twelve tribes of the sons of Israel are inscribed on the gates of the New Jerusalem (Rev. 21:12). This indicates that the Old Testament saints are the components of the New Jerusalem. Gates as the entrance into the city indicate that the Old Testament is the child-conductor who will lead the believers to Christ (Gal. 3:24). The Old Testament history of the twelve tribes of the sons of Israel leads us into the New Jerusalem through the pearl gates, which signify Christ who has died and resurrected.
The names of the twelve apostles are on the foundations of the wall of the New Jerusalem (Rev. 21:14). This indicates that the New Testament believers are also the constituents of the New Jerusalem. All the New Testament saints who have been led into Christ are being built upon the foundation of the apostles (Eph. 2:20), that is, being built upon the revelation which the apostles received for the building of the church, to become the wall of the New Jerusalem.
Revelation 21:2 and 9 clearly tell us that the New Jerusalem is the bride, the wife of the Lamb. In the whole Bible God repeatedly likens His chosen people to a spouse (Isa. 54:6; Jer. 3:1; Ezek. 16:8; Hosea 2:19; 2 Cor. 11:2; Eph. 5:31-32) for His satisfaction in love. As the wife of Christ, the New Jerusalem comes out of Christ to be His spouse, just as Eve came out of Adam and became his counterpart (Gen. 2:21-24). The bride is mainly for the wedding day, while the wife is for the entire married life. The New Jerusalem will first be the bride of Christ in the millennium for one thousand years as one day (2 Pet. 3:8), and then His wife in the new heaven and new earth for eternity. The bride in the millennium will include only the overcoming saints (Rev. 3:12; 19:7-9), but the wife in the new heaven and new earth will include all the redeemed and regenerated sons of God (Rev. 21:7).