Who or what is the city which descends (Revelation 21:9)?

[Markie51]

     This is a symbolic city that is made up of the 144,000 anointed, who were sealed “out of every tribe of the sons of Israel.” (Revelation 7:4-8; 14:1, 3)  In harmony with this, the foundation stones have on them the names of the 12 apostles of the Lamb. The New Jerusalem is not the fleshly nation of Israel founded on the 12 sons of Jacob.  It is the spiritual Israel, founded on “the apostles and prophets.”-Ephesians 2:20.

     In ancient times, city walls were built for security to keep out enemies. The symbolic city has a “great and lofty wall” shows that she is spiritually secure.  No enemy of righteousness, no one unclean or dishonest, will ever be able to gain entrance. (Revelation 21:27)  But for those allowed in, entering this beauteous city is like entering Paradise. (Revelation 2:7)  After Adam’s expulsion, cherubs were posted in front of the original Paradise to keep out unclean humans. (Genesis 3:24)  Similarly, angels are posted at each entrance of the holy city Jerusalem to ensure the spiritual security of the city.  Indeed, throughout the last days, angels have been guarding the congregation of anointed Christians, which becomes New Jerusalem, and without false religious practices and beliefs.-Matthew 13:41.