Is one of the seven angels the same angel who showed John the vision of Babylon in chapter 17? There is no way to be sure. The reference to a single angel in 1:1 and 22:16 suggests that it is, yet the angel now plays a somewhat different role. The vision of the holy city, unlike that of Babylon and the beast, is not a cryptogram that needs decoding. Consequently the angel is not an interpreting angel (as in 17:7-18). Instead, John supplies the interpretation himself (21:22-27; 22:3-5).
The angel promises to show John the bride, the wife of the Lamb (v. 9), but what then appears is a city, not a woman (v. 10). From this point on, the bridal imagery is dropped, to surface again only in 22:17. The image of the city as a woman is not carried through consistently, as it was in chapters 17 and 18. The angel shows John the holy city (vv. 9-14) and then measures it (vv. 15-21). The mountain great and high (v. 10) to which John is taken in the Spirit (that is, in his vision) is more than a vantage point from which to view the holy city. It is Mount Zion itself (14:1), on which the city stands, or rather "lands" in its descent from the sky.
The impression of enormous height in the reference to the mountain great and high is confirmed shortly when John sees a great, high wall surrounding the city (v. 12). In contrast to Babylon, situated in a "desert" (17:3), and in contrast even to "the city he loves," standing on "the breadth of the earth" at the millennium's end (20:9), this is a three-dimensional city, with length, breadth and height all equal. The traditional city laid out like a square becomes in John's vision a giant cube. The city is 12,000 stadia in length, and as wide and high as it is long (v. 16). Translated into modern measurements, this means almost fifteen hundred miles long, fifteen hundred miles wide and fifteen hundred miles high. Such a city defies both logic and imagination. Edwin A. Abbott, in his classic Victorian fantasy, Flatland: A Romance of Many Dimensions (1884), wrote of a two-dimensional world in which women were lines, working-class men were triangles, professional men were squares and priests were circles. The hero, "A Square," has a mystical experience in which a spherical Stranger ushers him into "the Land of Three Dimensions," transforming his flat world forever (Abbott 1952:80). John too looks into a city far beyond his comprehension or powers of description.
The angel's measurement (vv. 15-21) reveals that the city's great, high wall rises to a height of 144 cubits (about 216 feet), which is impressive enough for an ordinary city, but ridiculously small for a city 1500 miles high! Consequently the NIV renders the measurement as 144 cubits thick (see also Beckwith 1922:761). This is unlikely because (1) the first mention of the wall (v. 10) called attention to its great height, not its strength or thickness, and because (2) the wall is not built for protection or to keep people out, for its gates are always open (v. 25). Moreover, the word "thick" is not in the text, which says simply "144 cubits." The correct interpretation is "144 cubits high" (as in the NIV margin).
Despite the comparative modesty of 144 cubits, the intended effect is great height, as opposed to smallness or inadequacy. The measurement is not given for the sake of comparison with anything else. The great, high wall, like the great and high mountain of verse 10, simply calls attention to the strange fact that this city is three-dimensional. It has height as well as length and breadth. Such numbers as twelve thousand (stadia) and 144 (cubits) recall the 144,000 of chapter 7, with twelve thousand from each of the tribes of Israel: "a great multitude that no one could count, from every nation, tribe, people and language, standing before the throne and in front of the Lamb" (7:9). The huge cubical city has more than enough room for the 144,000 from Israel or even for a crowd without number from all nations. It encompasses the whole people of God. In some sense it is the people of God (Gundry 1987:254-64).
The notion of the city as people is conspicuous both in John's first sight of the city (vv. 9-14) and in the angel's measurement (vv. 15-21). First the angel shows John twelve gates in the city wall, three on each side, with twelve angels at the gates (vv. 12-13), and then, more briefly, the wall's twelve foundations (v. 14). On the gates John sees inscribed the names of the twelve tribes of Israel (v. 12) and on the foundations the names of the twelve apostles of the Lamb (v. 14). When the city is measured, the order is reversed: the twelve foundations are described first and at greater length (vv. 19-20), and then the twelve gates (v. 21). Each of the foundations is decorated with a different kind of precious stone, but there is no way to correlate these stones with whatever specific "apostles" John may have had in mind (John has no list of "the twelve apostles of the Lamb" comparable to his list of the "sons of Israel" in 7:5-8). As for the twelve gates, there is no differentiation among them. Each gate is a single pearl, all apparently alike and all evidently of enormous size. The "peoples" of God (see 21:3) have become a single people, one holy city.
Another conspicuous element both in the angel's presentation of holy Jerusalem (vv. 9-14) and in the act of measuring the city (vv. 15-21) is that the city reflects the character and the splendor of God in heaven. The city comes, after all, from God (v. 10). When John first sees it descending, it has the glory of God, and its brilliance was like that of a very precious jewel, like a jasper, clear as crystal (v. 11). When the angel has finished measuring the city, we learn that the city wall is made of jasper, while the city itself is pure gold, as pure as glass, with a street of pure gold, like transparent glass (vv. 18, 21). The comparison to jasper, with its indeterminate color, recalls the "someone" sitting on the throne in John's first vision of heaven (4:3, like "jasper and carnelian"). The phrases clear as crystal, as pure as glass, and like transparent glass echo the description of "what looked like a sea of glass, like crystal" in front of the throne in the same early vision (4:6). These varied expressions all make the point that the city radiates through and through the glory and purity of God, who made it and adorned it as the place for God and humans to dwell together in a world made new (see v. 3).