an excerpt from a book I am reading on Norse Paganism

"it is clear from such an array of source, which typically avoid direct articulation of key beliefs, no coherent account of Norse mythology can be extracted, and, indeed, there is no reason to assume that myths seek to express a single, orthodox belief. Mostly likely, there was considerable variety among religious ideas and attitudes of the Norsemen, who had no universal doctrine, no central church, and interestingly, no specfic word for religion. The closest concept was sidr, meaning custom, which reveals how integrated religion was in daily life. The multiple versions of specific myths and legends and often conflicting representations of principal gods like Odin and Thor suggest that beliefs of the Norsemen varied from region to region and that different people or communities found different gods appealing depending on familial, occupational, economic, regional, and cultural factors. Moreover, it is unlikely that the myths and religious practices of the Norsemen remained static or fixed at any given period of time and unsusceptible to outside influences. Unlike Christianity, the pagan Scandinavian religion was fluid and forebearing, and it never underwent the processes of open codification that characterized Christianity from its earliest stages and onward."

-Myths of the Norsemen, Introduction by Kirsten Wolf