A cross‐sectional study was conducted with 605 practitioners of Brazilian Jiu Jitsu ( BJJ) to test the hypothesis that high arousal rituals promote social cohesion, primarily through identity fusion. BJJ promotion rituals are rare, highly emotional ritual events that often feature gruelling belt‐whipping gauntlets. We used the variation in such experiences to examine whether more gruelling rituals were associated with identity fusion and pro‐group behaviour. We found no differences between those who had undergone belt‐whipping and those who had not and no evidence of a correlation between pain and social cohesion. However, across the full sample we found that positive, but not negative, affective experiences of promotional rituals were associated with identity fusion and that this mediated pro‐group action. These findings provide new evidence concerning the social functions of collective rituals and highlight the importance of addressing the potentially diverging subjective experiences of painful rituals.