But now thou askest me and sayest, "How shall I think on Himself, and what is He?" and to this I cannot answer thee but thus: "I wot not."
For thou hast brought me with thy question into that same darkness, and into that same cloud of unknowing, that I would thou wert in thyself. For of all other creatures and their works, yea, and of the works of God’s self, may a man through grace have fullhead of knowing, and well he can think of them: but of God Himself can no man think. And therefore I would leave all that thing that I can think, and choose to my love that thing that I cannot think. For why; He may well be loved, but not thought. By love may He be gotten and holden; but by thought never. And therefore, although it be good sometime to think of the kindness and the worthiness of God in special, and although it be a light and a part of contemplation: nevertheless yet in this work it shall be cast down and covered with a cloud of forgetting. And thou shalt step above it stalwartly, but Mistily, with a devout and a pleasing stirring of love, and try for to pierce that darkness above thee. And smite upon that thick cloud of unknowing with a sharp dart of longing love; and go not thence for thing that befalleth.
Cloud of Unknowing, Chapter 6
