Researchers and aid agencies, seeking to improve their understanding of local climate change responses, adaptation, and vulnerability, frequently interact with communities around the world who strongly emphasize their religious beliefs and practices. Dismissal and misunderstandings of these local perspectives can slow assessments of local climate vulnerability and development of adaptive capacity. In this paper, I show how analysis of rain ritual failure exposes the multiple stressors Ronga communities in southern Mozambique face, and as such, serves as a proxy measure for climate vulnerability at the local level. Oral histories and targeted interviews with participating elders, local chiefs, and community members documented local rain ritual practices and changes to these practices over the past 50 years. Emic descriptions of ritual practice, perceived changes, and explanations for ritual failure were analyzed with pre-determined and emergent codes and situated within the local and regional social, economic, political and environmental context to identify sources of community vulnerability. This research highlights the value of exploring local religious beliefs and practices when assessing local vulnerability and capacity for responding successfully to current and future climate uncertainty.