What is Christianity holy city?

Answer 1

Christianity has no holy city (not yet anyway). The gospel message is that the salvation of God has come to all the world. When the new heaven and new earth are revealed at the end, there will be a city. Until then, the so-called "holy cities" around the world are merely instances of pagan idolatry.

ANOTHER ANSWER:

What makes something "holy?" God's presence. God told Moses:

"...'take off your sandals, for YOU ARE STANDING ON HOLY GROUND.'" (Ex.3:5 NLT New Living Translation)

That piece of ground was "holy ground" because of God's presence.

What makes the LORD's seventh day of the week "holy?" It's because God MADE IT THAT WAY:

"On the seventh day... God BLESSED the seventh day and DECLARED IT HOLY, because it was the day when He rested from His work of creation." (Gen.2:2-3 NLT)

At one time in history, God referred to "Jerusalem" as His "Holy City"... back when there was a "divinely-established THRONE of a king there:

"The kings of the earth prepare for battle; the rulers plot together against the LORD and against HIS ANOINTED ONE [here's a reference to the "mortal kings" whom He caused to be anointed back in the day, as well as a future prophecy of the returning KING, Jesus Christ; against whom the nations of the world shall plot to defend themselves from His 'hostile take-over" of the earth, and pending world-wide rule - see Rev.17:12-14]... But the One who rules in heaven laughs. Then in anger He rebukes them, terrifying them with His fierce fury. For the LORD declares, 'I have placed MY CHOSEN KING on the throne IN Jerusalem, MY HOLY CITY.'" (Ps.2:2-6 NLT)

As the first answer alludes, however, there has been no "kingly God-appointed throne" in Jerusalem for millennia... and the city of Jerusalem is a far cry from being declared by God as anything approaching "holy" for a long time, now [His presence is simply not there]... despite what some men might declare to the contrary.

When Christ returns and sets up the headquarters of His throne in Jerusalem for His prophesied one thousand year rule [where the throne of David resided - see Luke 1:32]; His presence... the "presence" of God, there in Jerusalem, will "make Jerusalem HOLY" again... for that period of time.

But, as the Scriptures say... following the Millennial Rule of Christ, a "New Heaven and New Earth" will be created, and FROM OUT OF HEAVEN the TRUE HOLY CITY will descend upon the New Earth for which THE ENTIRE WORLD has really been waiting, if only in its Satan-blinded ignorance:

"...I saw a New Heaven and a New Earth, for the old heaven and the old earth had disappeared... And I saw THE HOLY CITY, NEW JERUSALEM, COMING DOWN FROM GOD OUT OF HEAVEN..." (Rev.21:1-2 NLT)

What makes the New Jerusalem "holy?" The presence of GOD THE FATHER, HIMSELF, sitting on the Holy City's throne:

"...'LOOK, the HOME OF GOD [the Father] IS NOW AMONG HIS PEOPLE [His Children]! HE WILL LIVE WITH THEM, and they will he His people [Children]. GOD [the Father] HIMSELF WILL BE WITH THEM... And the One sitting on the throne said, 'Look, I AM MAKING ALL THINGS NEW!' [a new creation is coming] And then He said to me, 'Write this down, for WHAT I TELL YOU IS TRUSTWORTHY and TRUE.'" (verses 3-5)

The holy city of "Christians" isn't just for so-called "Christians," but for all of mankind whom God created to be "reborn" into His Divine Family; the FAMILY OF GOD. That city is still IN HEAVEN - NEW JERUSALEM. God has yet to reveal it to His Children, other than through His written Word, which so few people have read about, much less believe if they do read about it.

And when the prophecies are finished... when "IT IS DONE" [see Rev.21: 6]... and the Children of the Family of God is finally revealed: and God's Divine, Immortal, All-Powerful Children begin colonizing and remaking the planets of the universe, which He made for them - His FAMILY OF CREATORS - then the entire universe will become HOLY... with THEIR PRESENCE!