Religious symbols, dramatized in rituals or related in myths, are felt somehow to sum up, for those for whom they are resonant, what is known about the way the world is, the quality of the emotional life it supports, and the way one ought to behave while in it. Sacred symbols thus relate an ontology and a cosmology to an aesthetics and a morality: their peculiar power comes from their presumed ability to identify fact with value at the most fundamental level, to give to what is otherwise merely actual, a comprehensive normative import . . . The tendency to synthesize world view and ethos at some level, if not logically necessary, is at least empircally coercive; if it is not philosophically justified, it is at least pragmatically universal.
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The force of a religion in supporting social values rests, then, on the ability of its symbols to formulate the world in which those values, as well as the forces opposing their realization, are fundamental ingredients. It represents the power of the human imagination to construct an image of reality in which, to quote Max Weber, ‘events are no just there and happen, but they have meaning and happen because of that meaning.’
Btw, there's an interesting discussion between Paul Bloom and Joshua Knobe on the topic of religion and morality over at blogginheads.tv which I recommend checking out.