After the millennial kingdom is concluded, the new heaven and new earth will come as the realm of God’s reign, the kingdom of God in eternity. God will reign in it forever and ever (Rev. 11:15), with the New Jerusalem as its center and the restored nations as its surroundings.
In the new heaven and new earth in eternity, the kingdom of God will be composed of two kinds of people: the saints, who are regenerated, as the sons of God (Rev. 21:7), and the nations, who will be restored, as God’s people (Rev. 21:3b). The regenerated saints as the sons of God will constitute the New Jerusalem to be God’s habitation in eternity (Rev. 21:1-3). The throne of God will be in it, from which God will reign to rule over the kingdom in the new heaven and new earth in eternity (Rev. 22:1, 3). All the regenerated saints throughout all the generations, whether perfected earlier or later, will be kings in the New Jerusalem (Rev. 22:5b) to enjoy the eternal blessings of God’s eternal life to the fullest extent. These blessings include the enjoyment of the illumination of God as the light of life for eternity (Rev. 21:23; 22:5), the enjoyment of the supply of Christ as the tree of life (Rev. 22:2a), and the enjoyment of the saturation of the Spirit as the water of life (Rev. 22:1; 21:6b). Thus, they will enjoy the riches of the processed Triune God to the fullest extent forever and ever.
In the new heaven and new earth, the restored nations will be around the New Jerusalem (Rev. 21:24) as the peoples in God’s kingdom for eternity (Rev. 21:3). Thus, the New Jerusalem will be God’s tabernacle among them. From it God will be their God and He will be with them. The saints, the sons of God, as the constituents of the New Jerusalem, will be kings to rule over them.
In the church in this age the believers receive God’s eternal life (John 3:15) and enjoy the blessing of the eternal life in the initial stage. In the heavenly part of the millennial kingdom in the coming age, the overcoming believers will inherit God’s eternal life (Matt. 19:29) and will enjoy the full blessing of the eternal life of God in a fuller way. In the New Jerusalem, the center of the new heaven and new earth in eternity, all the perfected saints will fully enter into the eternal life of God and enjoy the eternal blessing of God’s eternal life to the fullest extent for eternity. All three stages are the enjoyment of the eternal life of the processed Triune God in the kingdom of God.
The kingdom of God, like the church, is not an organization. It is an organism constituted with God’s divine life as the realm of life for His ruling, in which He reigns by His divine life and expresses Himself as the divine Trinity in the divine life. It began with the Old Testament saints and is realized in the church in this age. It will be completed in the New Jerusalem in the millennium and ultimately consummated in the New Jerusalem in the new heaven and new earth. God’s divine life, which is Christ Himself, is the seed of the realm of the divine life that develops into the kingdom for His ruling. As revealed in Luke 17:21, the kingdom of God is Christ Himself.
Christ, as the first seed of life of the kingdom of God, sowed Himself into His believers (Mark 4:3, 26) that He might grow and live in them and be developed from within them to bring forth many grains (Mark 4:20).
The believers, who receive Christ as the seed of the kingdom of God, also become seeds of life (Matt. 13:38), since they have Christ in them as their life. They grow and bring forth many grains by taking Christ as life; thus the kingdom of God is further developed. Such propagation and development will continue until the manifestation of the kingdom of God.