Religion's relationship to volunteering has been widely studied, with the majority of research indicating that religious 'belonging' (i.e., service attendance) matters more in motivating volunteering behaviour than religious 'believing' (i.e., personal importance of religion). However, research has not adequately examined the complex interplay of these facets of religiosity in a comprehensive longitudinal framework, looking at both inter- and intra-individual differences over time. Our study examines the individual and interactive effects of religious importance and service attendance, on both (1) volunteering likelihood, and (2) hours spent volunteering. Data from the Household Income and Labour Dynamics in Australia (HILDA) survey reveal that greater religious service attendance is associated with an increased likelihood of volunteering, whereas stronger religious importance is associated with an increase in time spent volunteering among volunteers. Findings suggest that a more nuanced view is needed regarding the ways in which different aspects of religion promote prosociality.