This chapter examines how religion influences interpersonal relationships and ethical dilemmas within team and coaching environments. It addresses coach-athlete dynamics, interfaith team interactions, and the complexities of faith expression in secular or multi-religious settings. Drawing on interviews and multicultural team studies, it demonstrates how shared religious values can enhance trust, cohesion, and mentorship, particularly when coaches are perceived as moral and spiritual role models. However, it also addresses challenges that arise when religious beliefs conflict, such as fasting during Ramadan, dress code controversies (e.g., hijab bans), or ritual-related scheduling conflicts. The chapter highlights cases where athletes felt excluded or misunderstood due to their religious identity and emphasizes the emotional and psychological toll of faith-based discrimination or microaggressions. Interfaith dynamics are also examined, including both positive (mutual respect and value sharing) and negative (tension, silence, and withdrawal) outcomes. Ethical considerations are explored through the lenses of sport psychology and ethics, advocating for a more inclusive and reflective approach to team communication, coaching styles, and organizational policies. Practical guidance is provided for coaches and consultants on how to navigate religious diversity respectfully, balancing performance goals with spiritual needs. This chapter contributes a comprehensive understanding of the interpersonal dimension of religion in competitive sport.