You know sometimes how one goes to see a church which one is told has magnificent windows--and seen from from outside they all look alike--dull, thick, grubby....Then we open the door and go inside--leave the outer world, enter the inner world--and the universal light floods through the windows and bathes us in their colour and beauty and significance, shows us things of which we had never dreamed, a loveliness that lies beyond the fringe of speech. And so in the same way we cannot realize God and all our Lord's lovely meaning as a revelation of God and His eternal Truth and Beauty from the outside....
It is from within the place of prayer, recollections, worship and love, where the altar is, where the sacrifice is made, where we are all bound together in a life of communion and self-giving to God, that we fully and truly receive the revelation which is made through Christ.
Light of Christ by Evelyn Underhill
Quoted in Philip H. Pfatteichers' New Book of Festivals & Commemorations