from The Science of the Cross
St. Teresa Benedicta of the Cross (Edith Stein)
The darkness that leads to God is, as we already know, faith. It is the only means that leads to union because it sets God before our eyes as he is: as infinite, as triune. Faith resembles God in that both blind the intellect and appear to it as darkness. "The greater one's faith the closer is one's union with God." Its darkness is indicated in sacred Scripture by the image of the cloud, in which God concealed himself in the Old Testament revelations: to Moses on the mount, in Solomon's temple. The light of truth is concealed in this darkness. It will "at once appear when faith reaches its end. . . by the ending of this mortal life."
Temporarily, though, we are totally dependent on faith. What it gives us -- contemplation-- is a dark and general knowledge; it stands in contrast not only to natural cognition but also to the various ways in which the intellect receives distinct and particular supernatural knowledge: visions, revelations, locutions, and spiritual feelings. The bodily eyes may be shown images and person from the other world: angels or saints, or unusual shining lights. One can hear extraordinary words, smell the sweetest fragrances, savor exquisite tastes, or feel extreme delight through the sense of touch. A person should refuse to attend to this, without seeking to examine whether it is good or bad. To be sure these things may come from God but there is no certainty about that. "God's self-communication is more appropriately given to the spirit than to the senses, and the soul finds greater security and make greater progress for through what is received by the sense, as a rule, great danger of deception exists. For the senses then believe they can arbitrate and judge spiritual matters, whereas they are as ignorant of them as a beast of burden is of rational matters."
Two points here: first, the image of the cloud occurs throughout all of mystical literature. One of the great early classics of English Spirituality is called The Cloud of Unknowing. This is a common inheritance.
Second: while God communicates to the soul all that the soul needs, because we are integrated creatures there is some fall-out perceived by the senses. That is, one may have visions or other extraordinary manifestations of what God is doing within. The best practice and soundest policy is to ignore the extraordinary without considering for a moment whether it is a sign of good or bad. Let go of it, let it slip by. The only important thing is continual focus on and ardent love of God. All of these things are extraneous, potential distractions; indeed, they are potential derailers of all the good that has come thus far. If one follows the senses and pays attention to these things as they occur, one strays once again from the giver and ends up pursuing the gift. The gift, as magnificent as it may be, is always less than the giver. The gift is merely a means to an end (or sometimes even less--a sign of the means), the Giver Himself is the end.