Despite the efforts of the Protestant churches to keep their members away from the ancestral culture and religion, Tsonga Christians of Mandlakazi in southern Mozambique still engage African ancestral beliefs and cosmologies to explain and deal with their existential situations, either covertly or openly. Why do they behaviour so, and what can theologians learn about these inter-religious experiences? To approach these questions, data were collected using semi-structural interviews and participant observation and analyzed through ground theory principles. The study will argue that, whereas the official Protestant discourse is concerned in building walls that preserve the purity of Christianity as a unique truth religion, these Tsonga Christians find religious differences as bridges connecting people. So, drawing from post-colonial thought, the study argue that too deal correctly with this religious mobility there is necessary a theological shift from the purity and incompatibility model to the intercultural one, based on two main assumptions. First, hybridism is not deviation or pathology, but the real nature of lived Christianity and therefore the starting point for any relevant and meaningful theology. Second, as human means of seeking well-being, religions are incomplete, and therefore, instead of competing, they should cooperate and complement each other.