The interface of religion, spirituality and mental health was investigated by conducting interviews with a group of Protestant evangelical pastors, and a group of registered counselling/clinical psychologists. The participants were selected through snowball sampling and were asked to describe their perceptions of, and experiences with religion, spirituality, and mental health in their respective positions as pastors and psychologists. The interview protocols were analysed through thematic analysis where themes were drawn from the data provided by participants. The data showed that both the pastors and the psychologists perceived a distance between the disciplines of religion, spirituality and mental health. The pastors described this distance as representing “two worlds”, a world of religion and spirituality and, a separate world of mental health. The psychologists similarly described an “unnamed conflict” that arises between the two worlds that can, at times, be characterised by perceived tension, discomfort and uncertainty. This tension has been amplified by the cultural climate of secularism in which religion had been marginalised and relegated to the private, rather than the public sphere of societal functions. With the shift to post-secularism has come greater acknowledgement of the role of religion and spirituality for individuals in society, bringing the necessity to consider the interface of religion, spirituality and mental health within mainstream psychological science. The data showed, however, that neither the psychologists nor the pastors had received formal training in this interface, which had resulted in high levels of ignorance and stigmatisation both between, and within the disciplines. Some of the stigmatisation about the interface of religion, spirituality and psychology could be attributed to the socio-political history of South Africa, making such stigmatisations indigenous to this country. Not only is training required on this interface, but as part of the findings of this study, an official position statement is proposed regarding Psychology’s approach to the interface of religion, spirituality and mental health, so that the proposed position statement can guide ethical psychological practice within the South African context. Despite the perception of the “two worlds” and the “unnamed conflict”, both the pastors and the psychologists agreed that collaboration between the two disciplines would be optimal, were committed to such a collaborative process, and provided suggestions about how that collaboration could be fostered. By naming the dynamics that characterise the “unnamed conflict”, greater levels of knowledge, transparency, respect, communication, openness, understanding, and ethical astuteness would serve to diminish the distance between the “two worlds”. / Psychology / Ph. D. (Psychology)