Wall
'A wall,' as in Revelation 21, signifies the divine truth proceeding from the Lord, and so, the truth of faith from the good of charity. 'A wall' signifies truth in outer extremes.
(Odkazy: Apocalypse Explained 21; Apocalypse Revealed 132)
Revelation 21:12
12
having a great and high wall; having twelve gates, and at the gates twelve angels; and names written on them, which are the names of the twelve tribes of the children of Israel.