This chapter explores the collision of categories in religious encounters, myths, and rituals. Laughter, which arises from incongruity, guides this exploration. Recalling encounters between European Christian missionaries and indigenous Africans in nineteenth-century South Africa, we find Africans often laughing at the missionary proposals to violate indigenous categories of gender, labor, hygiene, politics, and ancestral veneration. European commentators, from Christian missionaries to early anthropologists, interpreted African laughter as evidence of thoughtless ignorance. However, as an engagement with incongruity, laughter was actually a way of thinking about cultural difference. Recovering laughter as a resource for the study of religion, this chapter highlights incongruity in religious orientations and interreligious relations.