The great mystery of the divine incarnation remains a mystery for ever. How can the Word made flesh be essentially the same person that is wholly with the Father? How can he who is by nature God become by nature wholly man without lacking either nature, neither the divine by which he is God nor the human by which he became man? Faith alone grasps these mysteries. Faith alone is truly the substance and foundation of all that exceeds knowledge and understanding. (Saint Maximus the Confessor, +662)