Having the glory of God: meaning “shining with the light of the presence of God” (compare Ezek 43.5). For the glory of God see 15.8 (also comments at 1.6). One may also translate “It was shining (or, glowing) with the brilliant light that comes from God.”

Its radiance like a rare jewel: this radiance is a fuller description of the light that shines from the city: “It was shining like a precious (or, expensive) stone.” The adjective rare translates the Greek superlative form of the adjective “precious, costly,” as in the phrase “costly wood” in 18.12.

A jasper, clear as crystal: for jasper see 4.3; for crystal see 4.6a; 22.1. Translator’s New Testament translates “crystal-clear jasper.” In cultures where these stones are unknown, one may say, for example, “with a beautiful green and red light, just like clear transparent glass.”

Quoted with permission from Bratcher, Robert G. and Hatton, Howard A. A Handbook on The Revelation to John. (UBS Handbook Series). New York: UBS, 1993. For this and other handbooks for translators see here .