Scholars of Christianity in Korea have conventionally emphasized the proactive manner in which Koreans adopted and adapted this religion. In this formulation, the impact of missionaries is downplayed. In contrast, this article argues that not only did missionaries play a critical role in transmitting Christianity to the peninsula, but that they were also engaged in a fundamentally unequal partnership with Korean Christians. Fueling this inequality was the missionaries’ fear that many who sought to enter the church did so for impure motives. Thus, giving Koreans full control of the church was potentially dangerous. This article details one important strategy, the Nevius Method, employed by many Protestant missionaries to systematically test and probe Koreans in order to identify who were sincere and reform those who may have had selfish aims. The Nevius Method classified converts into a hierarchical system of church membership. But, while missionaries occupied the top positions, room existed for Korean Christians to contest missionary power. Keeping this dynamic in mind allows for a reinterpretation of important events in the history of Christianity in Korea, such as the P’yŏngyang Great Revival of 1907.