Research-practice partnerships around educational research may have beneficial outcomes but also present tensions. By considering the dynamics of manifested tensions, our study aims to understand how teachers engage with the various stages of the research in an inquiry-based professional development community consisting of eleven in-service teachers and three mathematics education researchers. In light of Heider's Balance Theory, we identify and analyze tensions expressed by teachers in the community discourse. Findings indicate that epistemic tensions related to teachers' and researchers' different cultural orientations act as powerful generators of inclusionary and exclusionary actions shaping community members' participation paths. While downplaying epistemic tensions can evoke individual actions detrimental to learning and destructive to the community's existence, awareness of and well-timed coping with tensions can become a springboard for community development.