For nurses of the nineteenth and early twentieth centuries, cleanliness was often seen as a virtue next to godliness. For missionary nurses, this analogy took on multiple meanings. This study focuses on discourses of cleanliness at one site of missionary nursing in the early twentieth century: the Rehoboth Mission and its hospital, which provided health-care to the Navajo in the southwestern USA from 1903 to 1965. Data sources included denominational publications, institutional records, correspondence, questionnaires and interviews of the Dutch-American missionary nurses who practiced at the Rehoboth Mission. Discourse analysis was conducted on references to cleanliness, hygiene and sanitation in these texts. Secondary discourses of embodiment in daily practice, initiation and assimilation, caring, ignorance, environmental factors and gendered work were identified and analyzed. The study interrogates the whiteness of the nurses' dominant culture and sheds light on nurses' relationships with normative discursive frames that reflect and perpetuate inequalities, discredit non-dominant practices, and leave little room for competing discourses. It also illustrates a blurring of religion and health-care, and the need for a reflective and informed stance as a basis for cultural competence.