The objective of this study was to explore the authentic knowledge that evolved from a spontaneously written personal diary and other texts of a person who committed a crime of passion. I attempted to demonstrate how spontaneous linguistic forms could be used to gain a better understanding of the dynamics underlying and precipitating a crime of passion. A crime of passion represents a part of reality where both the suffering individual and the therapeutic or researching community seem to be either out of control or very vague understanding and explaining this seemingly paradoxical phenomenon. The main question is: why is the knowing (loving a person) in such cases not revealed in their way of being (killing that person)? An existential-phenomenological approach was adopted to explicate the apparently paradoxical phenomenon of a crime of passion. I explored the complicated hidden meanings (knowledge) in the diary of a person who murdered his fiancée, to unravel these assumed paradoxes, and found that the knowledge (epistemology) in the subject spontaneous self-expression provided a key for a better understanding of his way of existence or being (ontology) within a specific context, time and part of his life. Exploratory, descriptive, conceptual and semantic questions were explored by adopting an existential-hermeneutical orientation that allowed me to explicate the paradoxes both at primary and secondary levels. Working from a qualitative research perspective and phenomenological methodology, an in-depth analysis of meaning units and conceptual categories clarified underlying and hidden meanings in the texts. Theoretical linkages between different conceptual categories were explicated, highlighting the gaps in our previous understanding and theorising about crimes of passion. In this I could reveal how the person s existence gradually changed from inauthentic (insincere) and pretending to a more authentic (sincere) life of caring and responsibility after the crime. The main contribution of this project can thus be described as providing new insights to the therapeutic and research community concerning the complexity of the paradoxical existence of a person who committed a crime of passion. / Thesis (PhD (Psychotherapy))--University of Pretoria, 2005. / Psychology / unrestricted