Morality and religion can be seen as internally related value systems: morality is concerned with everyday, cultural and political values, religion with ultimate values. Under the impact of the work of Jean Piaget, not only cognition, but also morality and religion have been conceptualized and researched as following a developmental progressive path in a person’s life time. However, the religious landscapes and value systems in Western societies have experienced changes toward a variety and complexity of developmental trajectories which pose challenges to the progressive developmental model and require new conceptual and methodological responses in the scientific study of religion and morality. It appears that our perspectives for understanding and our instruments in empirical research need an adjustment. Based upon James Fowler's faith development theory, but with reference to recent proposals in structural-developmental and life-span developmental psychology, I propose a model of religious styles which, in the first place, is the attempt to better account for the complexity of religious development, including its psychodynamic, interpersonal, life-history and life-world related dimensions. This model has consequences and includes also a perspective on moral development – which I shall explicate in regard to the attitudes toward the strange and unfamiliar religion and value system. Hundred years after William James' famous book, the question of the variety of religious experiences deserves new consideration and reflection, but the variety and complexity may have increased since then – also beyond North America and Western Europe.