This study analyses a Christic vision perceived by a woman during a radiotherapy session for her cervical cancer. A detailed description of the vision is presented based on a photographic documentation of the radiotherapy room, a painting of the vision made by the visionary herself and narratives retold two weeks after the vision, and again, one year later. Perceptual, social, and psychodynamic psychological theories are used to analyze the psychological prerequisites of the vision. It is shown that the vision is, in psychological terms, an illusion rather than a hallucination. Different possible origin mechanisms to the vision are discussed as well as why the vision is attributed to Jesus. The psychological function of the vision is analyzed with regard to the visionary’s religious behaviour and the role of this experience in coping with the cancer disease. It is argued that the visionary’s religious commitment is being strengthened and that the vision functions as a catalyst for previously-formed religious coping mechanisms. It also initiates at least one new kind of religious coping mechanism in the visionary’s coping system. A critical discussion of research methods concerning narratives of religious experiences is presented in the light of the results of the analyses undertaken in this paper where some problems with in-depth interviews conducted at one point in time are is highlighted. This kind of data collection appears more fragile when attempting to explain a phenomenon in terms of cause and events (in this case: the psychological prerequisites of the vision) than when trying to understand a phenomenon (in this case: the psychological function of the vision).