Through reforms in medical education, the practice of training standardized patients (SPs) for evaluating and educating medical students has been established. However, previous studies have tended to focus on the test performance of medical students. The initial motives of SPs, particularly their background and mission, have seldom been examined. The present study explored the views of SP volunteers regarding religious missions and the value of life they gain through their experiences of serving in a religious hospital. In-depth interviews were conducted with six volunteers who had at least 5 year of experience. According to our analysis, the motives of these volunteers were diverse. The following factors had a substantial influence on these SP volunteers, who had a religious background: the charisma of religious leaders and human relations in role-playing; emotional connections and cause-related marketing; and the ethical praxis in the ethnic Chinese belief system. Factors such as the social ethics in Confucianism, the view on philanthropy in Buddhism, and the idea of merit accumulation in popular religion had a considerable influence on these SP volunteers.