Freud regarded the monotheistic God as an illusion based upon the infantile emotional need for a powerful, supernatural pater familias. He maintained that religion – once necessary to restrain man's violent nature in the early stages of civilization – in modern times, can be set aside in favor of reason and science.[151] "Obsessive Actions and Religious Practices" (1907) notes the likeness between faith (religious belief) and neurotic obsession.[152] Totem and Taboo (1913) proposes that society and religion begin with the patricide and eating of the powerful paternal figure, who then becomes a revered collective memory.[153] These arguments were further developed in The Future of an Illusion (1927) in which Freud argued that religious belief serves the function of psychological consolation. Freud argues the belief of a supernatural protector serves as a buffer from man's "fear of nature" just as the belief in an afterlife serves as a buffer from man's fear of death. The core idea of the work is that all of religious belief can be explained through its function to society, not for its relation to the truth. This is why, according to Freud, religious beliefs are "illusions". In Civilization and Its Discontents (1930), he quotes his friend Romain Rolland, who described religion as an "oceanic sensation", but says he never experienced this feeling.[154] Moses and Monotheism (1937) proposes that Moses was the tribal pater familias, killed by the Jews, who psychologically coped with the patricide with a reaction formation conducive to their establishing monotheist Judaism;[155] analogously, he described the Roman Catholic rite of Holy Communion as cultural evidence of the killing and devouring of the sacred father.[89][156]
Moreover, he perceived religion, with its suppression of violence, as mediator of the societal and personal, the public and the private, conflicts between Eros and Thanatos, the forces of life and death.[157] Later works indicate Freud's pessimism about the future of civilization, which he noted in the 1931 edition of Civilization and its Discontents.[158]
In a footnote of his 1909 work, Analysis of a Phobia in a Five year old Boy, Freud theorized that the universal fear of castration was provoked in the uncircumcised when they perceived circumcision and that this was "the deepest unconscious root of anti-Semitism".[159]