To understand Christian architecture and therefore the Christian experience of divinity within space you need to travel all the way to the beginning. To the first international style in architecture.
Every architectural decision is a theological one.
There is a purely tactile quality in both sight and sound. It's through these that we reach that which is beyond us. As if our hand extended and mingled with the outside.
This is why both sight and sound are primordial in architecture and art as a whole. They are truly tools from the Outside, collecttive mechanisms of transcendence.
Mystics close their eyes and open their ears for the divine speaks in mute whispers. His voice broken.
Decoration is Noise. Bareness is Silence.
This is not to say that one is preferable over the other, but rather they encapsulate and embody the experience of the absolute and emptiness which defer not in kind but degree of intensity.
If God is the experience of the infinitely mysterious then its being must shine in the silence between signs. In the horror of abscence.
"Being does not see itself. Perhaps it listens to itself." —Gaston Bachelard
From retro science-fiction novels to today’s most popular Netflix series, future portrait in human mind is identified with ugliness and awfulness. Thus, brutalist buildings are seen as futuristic. Though brutalism is opposing to be pretentious. It features and shows the value of the material used for construction of a building instead of polishing and hiding it. In sum, it criticizes of the bourgeois comfort, sense of aesthetic, looking elegant and being cool as a “you are who you are” reaction.