The known plane is God's creation, fallen out of its union with Him, and therefore the world of the flesh needing redemption, the world of men, and of time, and of things — our world. This known plane is intersected by another plane that is unknown — the world of the Father, of the Primal Creation, and of the final Redemption. The relation between us and God, between this world and His world presses for recognition, but the line of intersection is not self-evident.

The Epistle to the Romans (1918; 1921)