This study explored the perspectives of mathematics teacher educator-researchers (MTE-Rs) on the use of theory in facilitating teacher growth. We adopted the framework of the theory-centered scholarship triangle (Silver & Herbst, 2007) to probe the underlying meanings of perspectives on theory use expressed by MTE-Rs. Qualitative analysis revealed three distinct types of perspectives: a perspective focusing on research, a perspective focusing on practice, and a perspective on the connection between research and practice. For the perspective on the connection between research and practice, two sub-categories were identified: connection with consideration of context and that without consideration of context. Different perspectives that MTE-Rs possess may influence their actions taken in professional development and consequently influence teachers' learning of theory. Specifically, the cyclic process of decontextualizing and recontextualizing theory between research and practice domains is the key to the development of MTE-Rs' educative power so that they can better facilitate teachers in learning theory.