The author, who taught architecture at a university for over 40 years, wrote this book out of his faith in religion, his hope for community, and his love for architecture.
The author reinterprets cathedral architecture, revealing that the cathedral is the “best social architecture,” “architecture that brings joy to all,” and “a house that speaks to the very essence of home” and the origin of community space.
Through photographs taken while visiting major cathedrals around the world, we examine in detail what cathedral architecture should be like and how cathedral space relates to liturgy.
This book will be an excellent guide for priests, believers, architects, and those interested in church architecture.

Le Corbusier's world-famous masterpiece, the Chapelle Notre Dame du Haut de Ronchamp, was heavily damaged by bombing during World War II in 1944. Much of the stone and concrete from the old chapel was reused as the walls of the new building.
This is because the stones and concrete of the old church were considered to be the body of the new church.
--- p.32

There is a monastery of Hosios Loukas in Phocida near Delphi, Greece.
This is the Byzantine-style Monastery of Venerable Luke (Hosios means Venerable, and Lucas is not the Evangelist Luke, but a hermit who died in 953). The Katholikon chapel inside is truly beautiful and filled with a mystical light.
This light represents the form in which God calls His people together, and the form in which people are called and gathered together.
--- p.106

The Abbey Church of Le Thoronet has all the features of Romanesque cathedral architecture condensed into a single small window shining behind the small altar in the east chapel.
The light coming through this small window is very strong.
The stone walls that form this window are very thick.
Even the slope of the stone, which was slanted inward like a trumpet and spread the light, became bright.
The light spreads outwards through the ironwork surrounding the window, spreading outwards towards the wider wall.
In this way, the vaults and walls surrounding the altar are filled with light.
--- p.140

He actually built a cathedral with parabolic walls.
The Holy Cross Church (Pfarrkirche Heilig Kreuz, 1957) in Bottrop, Germany is one such example.
A parabolic wall of carefully laid bricks surrounds the cathedral.
The large window at the front where the parabola begins resembles the top of a castle.
As we face the Holy Blood on the altar, we are at the bottom of the great chalice called the cathedral.
At this time, the altar and walls covered in darkness become the space of the Lord's suffering and pain.
--- pp.224-225

The cathedral is a space where the holiness of the altar spreads out and fills the area around the altar with its power.
The area around the altar refers to the floor, walls, and ceiling of the sanctuary.
The altar refers to a holy place (sanctuary) for worship within a church, especially the area around the altar.
The altar is a place like the Holy of Holies in Solomon's Temple, a place set apart from the body of the church and reserved for sacrificial offerings.
--- p.276

However, in our church architecture, there are quite a few churches that are designed to not provide sufficient spatial depth for the altar and to prioritize the believers looking at the altar from the congregation seats, as if in a theater.
The altar is actually quite shallow, but if a low, arched wall is placed in front of it, the altar's depth becomes weaker and its meaning diminished. Furthermore, in cathedrals with second-floor balconies where the congregation is located, the view from the altar can sometimes feel like a lecture hall or cultural space.
--- p.297

The prototype of cathedral architecture was the tabernacle.
Just as the power of God descends from above the cathedral to embrace the people, the tent-like ceiling embraces people.
The curved ceiling of the Longchamp Hall is famous for its representation of a tent.
The ceiling of Seoul's Banpo Cathedral is shaped like a tent, uniting the nave and the altar, showing the congregation as being within the power of God.
This is an excellent example of overlapping a slightly dark, low ceiling with a bright, high ceiling, creating the image of a long-axis cathedral on a hexagonal central plan.
--- p.355

Gaudi's Sagrada Familia is the ultimate cathedral, with its bell tower serving as both a structural element and a musical instrument, resonating both inside and out.
This cathedral has 18 tall towers.
The cathedral's façade features a tower of Jesus Christ supported by four metal columns above the crossing.
The height is 172.5m.
Next to it, four 130-meter-high towers dedicated to the four Evangelists surround the tower of Jesus Christ, and behind them, as if embracing this tower, stands the 130-meter-high tower dedicated to the Virgin Mary.
On top of these six towers are cimborios, structures raised to serve as skylights to let in light.

--- p.417