Apophatic theology

Apophatic theology, also known as negative theology, is a form of theological thought which attempts to approach the Divine by negation, to speak only in terms of what may not be said about the perfect goodness that is God.

Quotes

 * By positing God as unknowable, man excuses himself to what is still left of his religious conscience for his oblivion of God, his surrender to the world. He negates God in practice – his mind and his senses have been absorbed by the world – but he does not negate him in theory. He does not attack [God's] existence; he leaves it intact. But this existence neither affects nor incommodes him, for it is only a negative existence, an existence without existence; it is an existence that contradicts itself – a being that, in view of its effects, is indistinguishable from non-being. The negation of determinate, positive predicates of the Divine Being is nothing else than the negation of religion, but one which still has an appearance of religion, so that it is not recognized as a negation – it is nothing but a subtle, sly atheism. The alleged religious horror of limiting God by determinate predicates is only the irreligious wish to forget all about God, to banish him from the mind.
 * Ludwig Feuerbach, Introduction to The Essence of Christianity (1843), Z. Hanfi, trans., in The Fiery Brook (1972), p. 112