What is the City of New Jerusalem?
The City of New Jerusalem is the Holy City in the New Heaven and Earth that God has prepared for the saints who will participate in the first resurrection. After ending the plagues of the seven bowls on this earth, God would bind Satan in the bottomless pit for a thousand years, bestow the blessing of reigning with the Lord in the Millennial Kingdom on the saints who would have participated in the first resurrection, and after the thousand years are ended, make the first heaven and the first earth disappear and give the saints the gift of the New Heaven and Earth.
Those who are to receive these blessings are the saints who have received the remission of their sins by believing in the holy gospel of the water and the Spirit given by Jesus Christ. The Lord would become the saints' Bridegroom, and the saints, as the brides of the Lamb who has become their Bridegroom, would live in glory clothed in the Bridegroom's protection, blessing, and power in His glorious Kingdom.
God has prepared for these saints the Holy City in the New Heaven and Earth. This city is none other than the City of New Jerusalem. This is prepared solely for the saints of God. And this has all been planned for the saints in Jesus Christ even before the Lord God created the universe. Those who, by the amazing power of the Lord God, would live in the Millennial Kingdom of Christ are qualified to move to the New Heaven and Earth where the Holy City is found.
From this moment and on, the saints are to live with the Lord forever in the Temple of God. Because God is with them, there would no longer be death, nor sorrow, nor wailing, nor suffering, for the first heaven and the first earth would pass away, and God would make all things new.
The City of New Jerusalem shines, as it has the glory of God, and its light is like the most precious stone, like jasper stone, clear as crystal. God's glory is therefore with the city and those who are to live in it. The City has a great and high wall with twelve gates, three in each direction; the gates are guarded by twelve angels, and the names of the twelve tribes of Israel are written on the gates. The City's wall has twelve foundations, and on them the names of the twelve apostles of the Lamb are written.
The city is laid out as a gigantic square, with one side measuring 12,000 furlongs-equivalent to about 2,220 km (1,390 miles). Its wall measures 144 cubits, approximately 72 m. This wall is built with jasper, and the City is pure gold, like clear glass. The foundations of the wall are adorned with all kinds of precious stones, and the city's twelve gates are made of pearl.
Because the Lord God and the Lamb are in the City, there is no need for the sun or the moon to shine. Also, the river of the water of life flows from the throne of God and of the Lamb, wetting the Kingdom of Heaven and renewing all things. On both sides of the river stands the tree of life, bearing twelve fruits and yielding its fruits every month, and its leaves are for the healing of the nations. There are no more curses, but only eternal blessings are found there.