If you are a fortunate person, your local library might have the set of videos made by Joseph Campbell on "Mythologies" - came out in 1989. I've been re-watching them this past week, and they are exactly on point as to several of the questions raised here. Campbell has several books as well, and the most widely known is probably "The Hero With A 1,000 Faces."

There is an excellant book by Ruth Underhill called "Red Man's Religion", which surveys religious beliefs and practices of native american peoples. It has much broader applications, as well. Of particular interest in re this thread, she relates the nature of religion, or the organization thereof, to the size and stage of development of the society. She distinguishes between shamans and medicine men as religious leaders who gain their credibility through direct guidance from spirits, and priests, who gain their power and authority by adherence to ritual, originally created or describes by shamans and medicine men but often elaborated by the priestly class. If this dichotomy of shamans receiving spiritual guidance, and priests receiving power and authority through adherence to ritual, can be generally applied to the evolution of christianity, the person called Jesus would be viewed as a shaman, while those who came after and presumed to speak for him would be priests seeking, all too often power and authority, but occasionally, true holy men seeking and promoting spirituality. I don't wish to offend anyone here, merely to posit another view for contemplation.