This appears to be, among other things, an allusion/fulfillment of this prophecy of the new Jeruslaem:
[Psa 87:1-7 NASB] (1) A Psalm of the sons of Korah. A Song. His foundation is in the holy mountains. (2) The LORD loves the gates of Zion More than all the other dwelling places of Jacob. (3) Glorious things are spoken of you, O city of God. Selah. (4) "I shall mention Rahab and Babylon among those who know Me; Behold, Philistia and Tyre with Ethiopia: 'This one was born there.'" (5) But of Zion it shall be said, "This one and that one were born in her"; And the Most High Himself will establish her. (6) The LORD will count when He registers the peoples, "This one was born there." Selah. (7) Then those who sing as well as those who play the flutes shall say, "All my springs of joy are in you."
This may also be the background of references to the necessity of being "born over" aka "reborn" into the new Jerusalem through the new covenant which Paul describes as "the body of Christ" and John describes as a cubic city/temple:
[Rev 21:22-27 NKJV] (22) But I saw no temple in it, for the Lord God Almighty and the Lamb are its temple. (23) The city had no need of the sun or of the moon to shine in it, for the glory of God illuminated it. The Lamb is its light. (24) And the nations of those who are saved shall walk in its light, and the kings of the earth bring their glory and honor into it. (25) Its gates shall not be shut at all by day (there shall be no night there). (26) And they shall bring the glory and the honor of the nations into it. (27) But there shall by no means enter it anything that defiles, or causes an abomination or a lie, but only those who are written in the Lamb's Book of Life.
Paul describes this city as "the mother of us all";
[Gal 4:26 NKJV] (26) but the Jerusalem above is free, which is the mother of us all.