>In light of this, in your view, would Zech 14 or Isaiah 2 be a reference
>to this? Or would this be much later?
Actually, I don't think the legend of a heavenly jerusalem stems from
biblical times. My guess is, that it first came to existence during the end
of the second temple (300 BCE - 70 CE), otherwise we would have an explicit
statement in the bible. The biblical verses are just an "excuse" for the
midrash.