“And the twelve gates were twelve pearls, each of the gates made of a single pearl, and the street of the city was pure gold, like transparent glass. And I saw no temple in the city, for its temple is the Lord God the Almighty and the Lamb. And the city has no need of sun or moon to shine on it, for the glory of God gives it light, and its lamp is the Lamb. By its light will the nations walk, and the kings of the earth will bring their glory into it, and its gates will never be shut by day—and there will be no night there. They will bring into it the glory and the honor of the nations. But nothing unclean will ever enter it, nor anyone who does what is detestable or false, but only those who are written in the Lamb’s book of life.” (Revelation 21:21-27 ESV)

Here John struggles to describe another vision of the Church as the Bride of Christ. All the metaphors and symbols John uses to depict these details are human and earthly images and terms that symbolize theological truths and the ultimate reality the like of which John had never seen. The city is perfect in its dimensions, a perfect cube in shape unlike any human architecture. This symbolizes God’s perfection. The walls of the city are not needed for defense because all of God’s enemies have been defeated. Rather they symbolize God’s awesome power and strength. They also symbolize His and our separation from all that is unholy and sinful.
The basic building materials are those material things which we humans value most, what we consider to be most precious and beautiful: gold, pearls and precious gems. This tells us that God’s Kingdom is worth infinitely more than all that we strive for in life and all that we hold onto so dearly. Therefore it is worth all of our life, time, effort, sacrifice and suffering. In His kingdom we find peace, joy, solace, comfort, and healing from all the physical, spiritual and emotional pain we have endured in this life. We will never want for anything. We will never need to be afraid of anything. We will glory in the perfection of the Lord.