The perceived value of the integration of spirituality and religion (SR) in mental health care is growing. This study aimed to adapt an SR intervention developed in the USA (SPIRIT) for use in the Netherlands and to explore its applicability. Employing a participatory practice-based action research design, professionals, clients, and an advisory board collaborated in iterative cycles of translation, adaptation, discussion, and testing. The ongoing interfaith dialog during the adaptation process broadened the perspectives incorporated into the existing handouts. We added the term “meaning” (M) alongside SR to accommodate patients who do not identify with religion or spirituality. Additionally, several handouts were added to the original protocol: autonomy, responsibility, and liberty; loneliness and belonging; inspiring persons in the past and present; and grief and loss. Moreover, the existing handout on sacred verses was expanded to encompass versions from various outlooks on life: philosophical/humanistic, Judeo-Christian, Buddhist, Islamic, and Hindu. Finally, layout modifications and diverse exercise formats were introduced. A qualitative examination revealed that the adapted SPIRIT protocol was well received by professionals and patients, and quantitative studies on its applicability and usefulness are recommended.