Cultural and religious diversity has become a defining feature of societies worldwide. Although religious music serves as a powerful medium for fostering intercultural understanding, it remains underexamined in educational research. This systematic review analyzes studies published between 2016 and 2025, identified through comprehensive searches of SCOPUS, Web of Science, and ERIC databases. Eleven peer-reviewed studies meeting thematic criteria were selected for in-depth analysis. Findings revealed persistent challenges in religious music education, including policy ambiguity, teacher identity constraints, and limited resources. The review identifies a shift from traditional knowledge transmission to experiential pedagogies, leading to outcomes such as emotional resonance, intercultural understanding, moral self-regulation, and student agency. It also highlights structural gaps in longitudinal research and a significant underrepresentation of religious music traditions from Eastern Europe and other non-Anglophone regions. A practice–outcome heatmap developed in this study uncovered unexplored links, particularly regarding student agency. Future research should investigate these underexplored pedagogical–outcome pathways and address current geographic and cultural imbalances by incorporating regional traditions—such as Eastern European choral and sacred music—into global academic discourse.