The sun shall be no more thy light by day; neither for brightness shall the moon give light unto thee: but the Lord shall be unto thee an everlasting light, and thy God thy glory. (Isaiah 60:19)
The sun will not cease to exist when the earth is restored, but the city will no longer need it (Rev. 21:23; 22:5).
Everlasting light.
All Hebrew words following this phrase up to and including the same words in v. 20 are missing in Dead Sea scroll 1QIs. This is a clear case of a frequently occurring scribal error, called homoeoteleuton. The eye of the scribe unwittingly switched from the first occurrence of this repeated phrase to the second, and thus missed all the words between. The Dead Sea scroll 1QIs has this passage.