In Moses and Monotheism, Freud reconstructed biblical history by his general theory. His ideas were also developed in The Future of an Illusion. When Freud spoke of religion as an illusion, he maintained that it "is a fantasy structure from which a man must be set free if he is to grow to maturity."
Freud views the idea of God as being a version of the father image, and religious belief as at bottom infantile and neurotic. Authoritarian religion, Freud believed, is dysfunctional and alienates man from himself.