The bodily eye cannot see when it is in darkness or if it is blind. Just so, the soul, even with very excellent vision, cannot recognize anything unless God, her light, enlightens her. On the other hand, if her spiritual eye is blinded through sin or the desire for anything created, the divine light streams into it in vain. She does not recognize her darkness, that is, her ignorance… But when God has given the soul the light of grace, the eyes of her spirit are enlightened and open up to the divine light… transformation in God.
Saint Teresa Benedicta of the Cross