This paper aims to discover and discuss the place of spirituality in the meaning-making process for patients with life-threatening diseases like cancer. Does the search for meaning serve a specific role, or is it purely subjective? Finding constructive coping strategies can improve the quality of life. Meaning-making might be an essential coping strategy. Research has confirmed that spirituality is an integral part of meaning-making for many patients. To understand the findings of studies and their relevance for oncology and healthcare in general, definitions of religion, religiosity, and spirituality are presented. The main theoretical framework is shown in theories of the psychology of meaning. The search for meaning is discussed conceptually in psychoanalytic terms alongside developing a supporting super-ego. It aims to clarify the psychological effects and implications of faith, religion, religiosity, and spirituality on individual, interpersonal and social levels. The influence of illness on life and the impact of life on illness have to be considered, as cultural/societal challenges influence change processes. Internalization of a supportive super-ego, adequate self-regulation, and subjective illness perception/ "truth" influence (social) behavior (un)consciously. Therefore, a systems-theoretical view of the ability to accept boundaries should accompany the supporting super-ego in the process of the search for meaning. A bio-psycho-social model integrates all aspects of human life which are involved in dealing with a disease. The interest in the bio-psycho-social model is neither outdated nor new. The model is often supplemented by the factor of spirituality, which has been part of human experience throughout human history.