It would take almost a life-time of original research to fathom or approximately gauge the depths of ignorance in which the beginnings of Historic Christianity lie sunken out of sight.
It is the commonly accepted orthodox belief that Christianity originated with the life, miracles, sayings, and teachings; the birth, death, resurrection, and ascension of an historic Jesus the Christ at the commencement of our era, called Christian; whereas, the origins were manifold, but mostly concealed. It is impossible to determine anything fundamental by an appeal to the documents which, alone out of a hundred Gospels, were made Canonical. And when Eusebius recorded his memorable boast that he had virtually made "all square" for the Christians, it was an ominous announcement of what had been done to keep out of sight the mythical and mystical rootage of historic Christianity.