Ludwig Feuerbach 
The Essence of Christianity 

Religion is the disuniting of man from himself; he sets God before him as the antithesis of himself. God is not what man is—man is not what God is. God is the infinite, man the finite being; God is perfect, man imperfect; God eternal, man temporal; God almighty, man weak; God holy, man sinful. God and man are extremes: God is the absolutely positive, the sum of all realities; man the absolutely negative, comprehending all negations. But in religion man contemplates his own latent nature. Hence it must be shown that this antithesis, this differencing of God and man, with which religion begins, is a differencing of man with his own nature. The inherent necessity of this proof is at once apparent from this, —that if the divine nature, which is the object of religion, were really different from the nature of man, a division, a disunion could not take place. If God is really a different being from myself, why should his perfection trouble me? Disunion exists only between beings who are at variance, but who ought to be one, who can be one, and who consequently in nature, in truth, are one.