And the city had no need of the sun, neither of the moon, to shine in it - This imagery seems to be derived from Isaiah 9:19-20. See notes on those verses. No language could give a more striking or beautiful representation of the heavenly state than what is here employed.
For the glory of God did lighten it - By the visible splendor of his glory. See the notes on Revelation 21:11. That supplied the place of the sun and the moon.
And the Lamb is the light thereof - The Son of God; the Messiah. See the Revelation 5:6 note; Isaiah 60:19 note.

No need of the sun - This is also one of the traditions of the ancient Jews, that "in the world to come the Israelites shall have no need of the sun by day, nor the moon by night." - Yalcut Rubeni, fol. 7, 3. God's light shines in this city, and in the Lamb that light is concentrated, and from him everywhere diffused.

(16) And the city had no need of the sun, neither of the moon, to shine in it: for the glory of God did lighten it, and the Lamb [is] the light thereof.
(16) The second form of particular description (as I said) See Revelation 21:12 from exterior and outward actions which are these, light from God himself, to this verse glory from men, (Revelation 21:24). Finally such truth and incorruption of glory (Revelation 21:26) as can bear and abide with it, nothing that is inglorious, (Revelation 21:27).

And the city had no need of the sun, neither of the moon to shine in it,.... Which may be understood either literally of these two luminaries, which all earthly cities need; and which, though they may be in being in the new heavens, yet will not have the use with respect to this city they now have. The Jews say (u), the orb of the sun is in this world; and the gloss adds, but not in the future state, for the lights shall be renewed: and they further say (w), as here, that
"in the world to come, "Israel , will have no need of the light of the sun, nor of the light of the moon", neither by day nor by night,''
as they say (x), the Israelites had not in the wilderness. So they represent the Lord speaking to Moses, and saying (y),
"thy days shall cease, but thy light shall not cease; for thou shall have no need for ever of the light of the sun, nor of the light of the moon, and of the stars.''
Or else it may be understood mystically, but not of Christ, the sun of righteousness, whom the saints will always need and enjoy; but of the governors and discipline of the church in its present state; and of the written word, which is a light unto them now, and the ministration of it, and the ordinances of the Gospel, by which light and knowledge are conveyed; but in this state all will be immediately taught of God; nor shall everyone teach his neighbour, but all shall know the Lord perfectly; and also of political governors, who will be no more; see 1-Corinthians 15:24.
For the glory of God did lighten it; the Shekinah, or glorious presence of God, which filled the temple of Solomon, and shone round about the shepherds at the incarnation of Christ; with the presence of God, who is light itself, which will be enjoyed in a much more glorious manner, will the church now be enlightened; and this will be an everlasting light unto her: and the Lamb is the light thereof; in whose light they will see the face of God, and see God face to face; they will see Christ as he is, and behold his glory; and look upon the angels, those glorious forms of light, and all the glorified saints, and know and converse with each other; and they will look into, and clearly discern all the mysteries and doctrines of grace, and all the various scenes of Providence, which will all be opened and laid before them. And this light will be always without any change and variation; which is no small part of the commendation of this city, which is the inheritance of the saints in light. So the holy blessed God is said by the Jews (z) to be , "the light of Jerusalem"; he is the light of the new Jerusalem; see Isaiah 60:19 and the light of, the world to come is, by (a) them, called "the great light".
(u) T. Bab. Sanhedrin, fol. 101. 1. (w) Raziel, fol. 17. 2. (x) Yalkut Simeoni, par. 2. fol. 57. 2. (y) Petirat Moseh, fol. 23. 2. (z) Yalkut Simeoni, par. 2. fol. 57. 2. & 98. 1. (a) Ben Gorion apud Aben Ezram in Psal. xlix. 19.

in it--so Vulgate. But A, B, and ANDREAS read, "(shine) on it," or literally, "for her."
the light--Greek, "the lamp" (Isaiah 60:19-20). The direct light of God and the Lamb shall make the saints independent of God's creatures, the sun and moon, for light.

The glory of God - Infinitely brighter than the shining of the sun.