Google Kaymakli Underground City.
Many early Christians hid from persecution in caves in the weird, wind swept talc-mountains of Cappodocia.
I remember reading about them, and seeing color photographs of those cave-cities, with huge vaulted rooms connected by tunnels, and elaborately frescoed cathedrals, all of it underground.
To think that the first Christians produced men like St. Basil who were capable of contemplating the mind of God, and writing about it, all while living and worshipping in such treacherous terrain...well it all quite boggles my puny mind!
Thanks for posting, NRx!
You wrote “the unknowable essence of God”
this is answered in Isaiah 11:2 The first Spirit of the 7 spirits of God listed there .
Jesus said all the law and the prophets hang on this one Spirit of The Lord