Tolkien on the Presence of God in the Lord of the Rings

You... create a world in which some sort of faith seems to be everywhere without a visible source, like light from an invisible lamp. -- J.R.R. Tolkien quoting an "unbelieving" reader in letter no. 328, The Letters of J.R.R. Tolkien, Ed. Humphrey Carpenter. (HT: The Flame Imperishable)