The view that the physical body is evil and detrimental to a holy life and that only through renunciation of the world can one reach a higher spiritual state.

asceticism - (from Greek askeo: ''to exercise,'' or ''to train''), the practice of the denial of physical or psychological desires in order to attain a spiritual ideal or goal. Hardly any religion has been without at least traces or some features of asceticism.
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The Corinthian ascetics think that spirituality is antithetical to the enjoyment of sex within marriage. Paul wants his readers (which includes us) to understand that spirituality encompasses every aspect of one’s life, including sex.