That the faith is shadowy is a blessing, it tempers the light to the eye’s weakness and prepares the eye for the light; for it is written: “He cleansed their hearts by faith.” Faith therefore does not quench the light but protects it. Whatever it may be that the angel sees, is preserved for me by the shadow of faith, stored up in its trusty breast, until it be revealed in due time. If you cannot yet grasp the naked truth is it not worthwhile to possess it wrapped in a veil? Our Lord’s Mother herself lived in the shadow of faith, for she was told: “Blessed are you who believed.” Even the body of Christ was a shadow for her, as implied in the words: “The power of the Most High will cover you with its shadow.” That is no mean shadow which is formed by the power of the Most High. Assuredly there was power in the flesh of Christ that overshadowed the Virgin, since by means of the envelope of his vivifying body she was able to bear his majestic presence, and endure the unapproachable light, a thing impossible to mortal woman. That was power indeed by which every opposing might was overcome. Both the power and the shadow put the demons to flight and became a shelter for men: an invigorating power surely, a shadow radiating coolness. We therefore who walk by faith live in the shadow of Christ; we are fed with his flesh as the source of our life. For Christ’s flesh is real food.
Bernard of Clairvaux, On the Song of Songs II, Sermon 31: The Various Ways of Seeing God, v. 9, 10 (CF 7, p. 132)