"The heavenly messenger measured the holy city and it was twelve thousand furlongs or fifteen hundred miles: the length and the breadth and the height of it were equal, as we have pointed out — a cube. Some have supposed that a literal city must be meant since various measurements are given. However, we must always keep in mind that this city is the bride, the Lamb’s wife! Therefore such dimensions must necessarily have a symbolical and spiritual meaning in relation to the body of Christ! The measurements are in multiples of twelve which are a symbol and signature of God’s purposes in His elect. The number twelve often enters into the symbolism of the book of Revelation — twelve tribes, twelve stars, twelve apostles, twelve angels, twelve foundations, twelve gates. So here the number twelve is found in the measurements of the city: each side is twelve thousand furlongs and the wall is one hundred and forty-four cubits, which is twelve times twelve."
Much more in the link:
https://www.godfire.net/eby/Rev/rev246.html
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"We also learn in the formation of this city of gold and putting nothing in it but the best, that we must begin with the foundation just as every builder does. Paul tells us about the foundation, that it is Jesus Christ. In another sense, in the Revelation, it is the apostles of the Lamb. Now how can both be true? The answer is not difficult to find. When the life, nature, faith, wisdom, and power of the Lord is laid in our lives the foundation is laid in us — that is Jesus Christ. Paul well knew his calling. It had been from heaven and after God revealed it to him, Paul didn’t go and ask the other apostles what they thought about it, but got busy right away with getting the foundation laid first in his own life, and then in those he ministered to. Thus he said, "I am determined to know nothing among you save Jesus Christ and Him crucified." And that is the foundation for every saint of God who will press on to the glory and majesty of the holy city, the precious stone that has been laid in the earth, the tried stone, the sure foundation that will never fail. The dread infirmity of the Lord’s people is just this — that not only are they oft times building with inferior materials of wood, hay and stubble, but many are not building on the true and only foundation of JESUS CHRIST. The foundation is not a generic Christ, nor some cosmic Christ, nor the Christ principle — it is JESUS CHRIST and none other. It was Paul’s lot to lay the foundation in men which is nothing else but Jesus Christ the Lord!"
"Twelve is the number of divine government. One thousand is the number signifying the day of the Lord (II Pet. 3:8). Twelve times one thousand is God’s light and illumination (day) multiplied by God’s authority and rule (government) — the perfect and full dominion of God by the revelation of His glory without mixture, limitation, or darkness. The Holy of holies of God’s eternal kingdom is, therefore, in type, 528,000 times more glorious than the Holy of holies in the Mosaic tabernacle that was a cube of only ten cubits or fifteen feet each way! The true measure of the city is the Lord Jesus Christ: "…unto the measure of the stature of the fullness of Christ" (Eph. 4:13). The people who come to this measure will be the glory of God, the perfection of beauty, and the light of the world in the fullness of what that means, and will bring the total restoration that God, who cannot lie, has promised to all creation. Hallelujah!"
"Then I was made to know that the "twelve legions of angels" of which Jesus spoke is a symbol for the army of God. This knowledge stirred me tremendously! Think not, dear friend, that Jesus meant that He could call an exact number of heavenly messengers, for the number of soldiers in a legion was not fixed — it could run anywhere from about 3,000 to more than 6,000 men. Twelve is a symbolic number, a perfect number, a meaningful number, signifying GOVERNMENTAL PERFECTION. It is found as a multiple in all that has to do with RULE. Ed Vallowe, in his splendid book KEYS TO SCRIPTURE NUMERICS, has written, "This number, twelve, symbolizes God’s perfect, divine accomplishment actively manifested. It shows a completeness of a growth or administration. Twelve marks governmental perfection and is used as the signature of Israel. The number is used 187 times in the Bible. It is used 22 times in the book of Revelation. Twelve is the number for government by divine appointment. Jesus said to His disciples, Verily, I say unto you, that ye which have followed me, in the regeneration, when the Son of man shall sit in the throne of His glory, ye also shall sit upon twelve thrones, judging the twelve tribes of Israel’ (Mat. 19:28). The twelve apostles shall sit upon their twelve thrones and judge and rule in connection with our Lord’s rule upon His throne. They will occupy those twelve (symbolical) thrones by divine appointment."
Long quote in the link :)
https://www.godfire.net/eby/Rev/rev246.html
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