This article explores how Islamic religious practices are facilitated and experienced in two Flemish prisons. Drawing on ethnographic fieldwork and forty semi-structured interviews with Muslim individuals in detention and ten prison officers, it examines the measures both institutions take to enable religious practice and how these accommodations are perceived. Muslims reported finding support, peace and meaning in their faith, but also pointed to practical obstacles and inequalities in its organisation. Staff members largely acknowledged the positive impact of religious practices on individual behaviour but also expressed concerns about group formation and logistical challenges. Central to this study is the practice of prayer, which could be a source of both support and conflict. By bringing together both perspectives, the article offers a nuanced insight into the religious dynamics within prisons and the tensions that arise between spiritual needs, institutional logics and security considerations.