Revelation 21:15

And he measured the city, twelve thousand furlongs — Not in circumference, but on each of the four sides. Jerusalem was thirtythree furlongs in circumference; Alexandria thirty in length, ten in breadth. Nineveh is reported to have been four hundred furlongs round; Babylon four hundred and eighty. But what inconsiderable villages were all these compared to the new Jerusalem! By this measure is understood the greatness of the city, with the exact order and just proportion of every part of it; to show, figuratively, that this city was prepared for a great number of inhabitants, how small soever the number of real Christians may sometimes appear to be; and that everything relating to the happiness of that state was prepared with the greatest order and exactness.

The city is twelve thousand furlongs high; the wall, an hundred and forty — four reeds. This is exactly the same height, only expressed in a different manner. The twelve thousand furlongs, being spoken absolutely, without any explanation, are common, human furlongs: the hundred forty — four reeds are not of common human length, but of angelic, abundantly larger than human. It is said, the measure of a man that is, of an angel because St. John saw the measuring angel in an human shape. The reed therefore was as great as was the stature of that human form in which the angel appeared. In treating of all these things a deep reverence is necessary; and so is a measure of spiritual wisdom; that we may neither understand them too literally and grossly, nor go too far from the natural force of the words. The gold, the pearls, the precious stones, the walls, foundations, gates, are undoubtedly figurative expressions; seeing the city itself is in glory, and the inhabitants of it have spiritual bodies: yet these spiritual bodies are also real bodies, and the city is an abode distinct from its inhabitants, and proportioned to them who take up a finite and a determinate space. The measures, therefore, above mentioned are real and determinate.