In recent decades, the Egyptian public sphere has witnessed increasing and sometimes heated discussions around mental disorders like depression and obsessive compulsive disorder (OCD). These debates, carried out among psychiatrists, religious scholars and Quranic healers, have centered on the question whether such afflictions are due to neurochemical brain imbalances and life’s stresses or to the devil’s temptation coupled with a person’s weak faith. The significance of these arguments lies in their articulation of diverse understandings of affliction, causation and reality that point to the different ontologies at work in contemporary Egypt and to a society-wide reflection over the boundaries between science and religion. This presentation analyzes the debates surrounding the conceptualization of and the relationship between OCD (al-wasw?s al-qahr?) and devil’s whispers (wasw?s al-shay??n), focusing on the positions of psychiatrists and of the practitioners of a popular form of treatment with the Quran known as Quranic healing (al-‘il?g bi-l-Qur’?n). On the basis of interviews and the analysis of published materials, one can distinguish two main positions emerging in these debates. The first involves drawing an ontological equivalence between OCD and the devil’s whispers. For some Quranic healers what psychiatrists identify as OCD is in fact the devil’s whispers to which a weak self gives course. In this way a psychological and physical affliction is transformed into a moral one denying in the process the validity of psychiatric diagnoses. The symmetrical opposite is the claim of some psychiatrists that what Quranic healers take as the devil’s whispers is in fact OCD. According to the second position, adopted by both psychiatrists and Quranic healers, there are two types of ‘whispers’—pathological and the devil’s— and therefore two distinguishable afflictions with overlapping symptoms each with its own etiology and forms of treatment. In this way, both Quranic healers and psychiatrists see OCD and the devil’s whispers as sometimes coexisting and other times as mutually exclusive. The coexistence of these different perspectives and the debates themselves point not to a clear-cut relation between psychiatry and forms of religious healing, but to dynamic, ongoing processes of redefining what is physically versus morally treatable and of redrawing the boundaries between what counts as religious and what as scientific in relation to mental disorders. It is through such processes that both psychiatric and Islamic traditions are remade in contemporary Egypt.