Over the past two decades, in response to a growing awareness of the impacts of humanitarian crises on mental health and psychosocial well-being, leading UN agencies and international aid organisations have developed a comprehensive framework for Mental Health and Psychosocial Support (MHPSS). In more recent years, aid workers have further begun to consider religious life as a central factor in mental health and psychosocial well-being, viewing “faith” as an important, but often neglected, component of empowering and “locally appropriate” MHPSS. However, the attempt to deliver “faith-sensitive” MHPSS across the highly pluralistic settings of international humanitarian intervention has entailed protracted ethical and practical challenges. In this article, we argue that these challenges may be usefully understood in terms of three areas of concern: the lack of evidence on effective interventions; the risk of reproducing problematic power dynamics between MHPSS providers and receivers; and the challenge of articulating a cross-culturally relevant paradigm of “faith-sensitivity” comprehensible across a wide range of religiously diverse settings. This article contributes to these challenges by drawing on the field of professional spiritual care to suggest areas of potential contribution and interdisciplinary dialogue.