Metaphor is not a completely successful or controllable means of communication. People can employ only inadequate language where God is concerned, and metaphor is the best method at their disposal, because it allows the mind to get around barriers by subtle and indirect means. “We therefore make the subject clearer, and show to the understanding the way of truth by saying He is one but does not possess the attribute of unity.” This seems to contradict ordinary expression, but by negating part of the phrase in the figurative statement, the sensitive mind passes on to a grasp of God’s nature, which could not be given by direct statement. What we learn from this example is that “we cannot describe the Creator by any means except by negative attributes.” Metaphor and negative theology, then, are natural companions.
Positive assertions about God allow the imagination to mislead one, whereas proof by negation leads one gradually to more perfect knowledge of God. The mystery involved in the divine nature turns the ordinary situation around, so that one can be convinced that certain qualities must be negated, whereas one cannot be as sure of positive attributes as one might be in an ordinary instance. The method of negative attributes is necessary “to direct the mind to the truth that we must believe concerning God,” but it could be adopted only by one who felt the presence of mystery in the divine nature and realized the inappropriateness of frontal attack.
One’s only complete knowledge concerning God, it turns out, “consists in knowing that we are unable truly to comprehend Him.” God alone comprehends himself, and one not made aware of these matters too quickly jumps to the conclusion that people can know nothing about God at all. The truth lies somewhere in between, and it requires the energy of religious interest to keep from slipping into either extreme. God may be approached, but only by indirection. The negative method provides the mind with positive apprehensions of the divine nature but not such that all mystery is removed because God remains never fully comprehended by any being other than himself.