Researchers have found religiosity and gender ideology to be associated with higher relationship quality. These associations between religiosity, gender ideology, and relationship quality are likely mediated by three dimensions of relationship commitment. The current study uses data from the 1999 wave of the Family Transitions Project (N = 290) to test the mediating effects of relationship commitment for individuals and couples. Among the findings, there were indirect effects of religiosity and traditional gender ideology on relationship quality through personal commitment for individuals. For couples, there was a positive indirect effect of attendance on relationship quality through personal commitment, but a negative indirect effect of gender ideology through personal commitment. In the model with religious beliefs, there was a positive direct effect of gender ideology on relationship quality. These results emphasize the importance of considering the influence of relationship commitment in explaining the associations between religiosity, gender ideology, and relationship quality.