Yes, the heavenly Jerusalem is the `mother of us all.` And the heavenly Jerusalem is made up of two parts, (as is the earthly one). The city is NOT on the hill but further down. They are separate. King David had the ruling part on Mount Zion and the people were in the city further down.The Jerusalem (city) that is above is our mother as the apostle wrote. He got this from the OT scripture that says we are born in Zion..."this one and that one were born in her"...Zion being referred to as a "her" because she is a mother. They are both allegories for the same thing, which we must understand that it is not a literal city or mount, they are just allegories for Christ and His collective church/body and kingdom in heaven, ie, heavenly. It is a city on a hill/mount (Zion)...because being spiritual/heavenly it is higher than the earthly
1. Mount Zion - the ruling part. Christ`s own throne. (Ps. 2: 6)
2. The city - for the OT saints. (Heb. 11: 16)