"I think that this experience you are having of losing your faith, or as you think, of having lost it, is an experience that in the long run belongs to faith; or at least it can belong to faith if faith is still valuable to you, and it must be or you would not have written to me about this.

I don’t know how the kind of faith required of a Christian living in the 20th century can be at all if it is not grounded on this experience you are having right now of unbelief. This may be the case always and not just in the 20th century. Peter said “Lord, I believe. Help my unbelief”. It is the most agonizing prayer in the gospels, and I think it is the foundation prayer of faith."