Amos is talking about the 'New Jerusalem' that desends from Heaven at the end of the age after the White Throne Judgement. See Revelation 21:1,2: Then I saw a new earth (with no oceans!) and a new sky, for the present earth and sky had disappeared. And I, John,saw the Holy City, the new Jerusalem, coming down from God out of heaven. It was a glorious sight, beautiful as a bride at her wedding. Quoted from 'The Way', The Living Bible-Illustrated by Tyndale, 1972 edition. Thank you, Amos.
from the article: Dreaming of the Third Temple in a conflicted Land of Israel