No human words can describe it fully, because the Church itself is part of the Mystery of Christ.
The Eschatological Church started before the creation of the World and it will last forever
We have a clear paint of it in Revelation 21
21:9 Then came one of the seven angels who had the seven bowls full of the seven last plagues, and spoke to me, saying, "Come, I will show you the Bride, the wife of the Lamb."
21:10 And in the Spirit he carried me away to a great, high mountain, and showed me the holy city Jerusalem coming down out of heaven from God,......
21:22 And I saw no temple in the city, for its temple is the Lord God the Almighty and the Lamb.
The altar, the High Priest and the scrifice are the same: Christ
This church, if imitated too much, it becames the Church of the "already Saints"
The Visible Church started at Pentecost when the Holy Spirit arrived one it, and it will last till the return of Christ.
1Cor10:16 The cup of blessing which we bless, is it not a participation in the blood of Christ? The bread which we break, is it not a participation in the body of Christ?
The altar if the stone altar we find in the Church-buildings, the priests are the successors of the Apostoles, the sacrifice is the Blood and the Body of Christ (the Eucharist)
This church, if imitated too much, it becames the Church of the "bishops"
The Personal Church started at your baptism, and it will last till, in the heaven, you will be in Christ and Christ in you ( John 4:20)
Romans 12:1 I appeal to you therefore, brethren, by the mercies of God, to present your bodies as a living sacrifice, holy and acceptable to God, which is your rational worship.
1Peter 2:5 and like living stones be yourselves built into a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ.
1Cor 6:19 Do you not know that your body is a temple of the Holy Spirit within you, which you have from God? You are not your own;
So here the temple is your heart, your body, the priest is yourself (priesthod of all believers), the sacrifices are you good deeds , your prayer, your crosses
This church, if imitated too much, it becames the Church of the "ascetic life"
A good christian life includes all these three churches, in a equal balance.