Judeo-Christian tradition?

Just what is this Judeo-Christian tradition anyhow? Did Christianity even have any Jewish origins at all?

Christianity appears to be largely based on man-god mythology, a recurring theme in Indo-European mythology, especially Celtic, pre-Zoroastrian Persian, and Indus Vally mythology. The idea that any God could ever appear in human form is utterly alien to Semitic mythology and downright blasphemous to Judaism.

Now, let's look at this list of more than half of the groups to whom Saint Paul addressed epistles: Colossians, Corinthians, Ephesians, Galatians, Philippians, Thessalonians. Notice anything special about these groups? Yes, they're all in the fringe zone where Greek and Celtic civilizations overlapped. (In fact, the Galatians were entirely Celtic.)

Now, sometime when you haven't got anything to do that's worth doing, sit down and read these epistles. One of Paul's main aims appears to be to get them all to agree on a set of beliefs. It appears that all these groups had already developed their own separate man-god mythologies and Paul saw some value (perhaps political) in uniting them.

Here's another hint: the early Christians used the Septuagint as their version of the Jewish scriptures. The Septuagint was written for the benefit of Greeks wanting to learn about the traditional literature of their Jewish neighbors, and was never considered canonically sacred by any Jews, not even Greek-speaking Jews. There were other Greek translations of Jewish scriptures in use by Greek-speaking Jews.

And yet another hint: all four Gospels were written by people who appeared to have a rather poor knowledge of the geography of Palestine and the customs of Aramaic-speaking Jews in Palestine.

Here's my conjecture, which I'll admit I can't prove, but I think it sounds plausible. Soon after 36 AD when Pontius Pilate was relieved of his political career under highly scandalous circumstances, a number of existing Greek-Celtic man-god cultists (who had, for more than a century, been using the Greek title Christ, meaning Anointed One, to refer to their man-god) decided that Pontius Pilate would be the perfect ruler for their man-god to have been crucified by. Therefore, they had to make a few hasty modifications to their myths to give their man-god a Palestinian Jewish identity. Their meager knowledge of Jewish things was just barely good enough to fool the uneducated masses who formed the entirety of early Christianity.

So, it looks to me like Judaism was simply crammed onto the front end of Christianity as a convenient afterthought.