African faith-based organization (FBO) leaders influence their members’ HIV knowledge, beliefs, and practices, but their roles in HIV prevention and care are poorly understood. This paper expands the work of Garner (2000) to test the impact of FBO influence on member risk and care behaviors, embedding it in the Theory of Planned Behavior. Qualitative interviews and quantitative surveys were collected from 5 FBOs (Christian and Muslim) in Malawi and analyzed using mixed methods. Contrary to Garner, we found that the level of power and influence of the FBO had no significant impact on the risk-taking behaviors of members; however, leaders’ HIV knowledge predicted members’ behaviors. Stigmatizing attitudes of leaders significantly decreased members’ care behaviors, but FBO hierarchy tended to increase members’ care behaviors. The power of local church/mosque leaders to influence behavior could be exploited more effectively by nurses by providing support, knowledge, and encouragement to churches and mosques.