This project explores the experiences of cognitive dissonance caused by the sexual activity of unmarried Christian adults in the UK. It identifies processes of the formation, negotiation, and maintenance of participants’ religious identities, and the impacts that sexual activity has on these processes. Using anonymous narratives, autoethnographic material, and semi-structured interviews, it uncovers some of the impacts these experiences had on their religious beliefs and their relationships. In doing so, it highlights potential causal factors for young adults distancing themselves from the Church and limiting its authority over their lifestyle choices. The dissertation argues that unmarried Christians experience their sexual selves through complex and interlinking processes of negotiation between beliefs, actions, and identities. It states that the process of negotiation is often a painful one due to experiences of cognitive dissonance, which usually has vast implications on the believers themselves, their sexual partner/s, and their church communities. It suggests that establishing firm beliefs about sex outside of marriage prior to sexual opportunities is vital in order to avoid this. Finally, it suggests that the Church could potentially enable this by encouraging thorough, open, and honest dialogue about sex and marriage.