Nobody doubts that Christians existed in the 1st century. But the fact that they may have had various disagreements amongst themselves is hardly any sort of evidence that Jesus was real.
The disagreements between Gnostics and those who came to be orthodox Christians (i.e. the sect that won and therefore wrote the history) would fit this view. The disagreements we find in Galatians, which were smoothed over in Acts, had to do with whether or not new converts to Christian belief had to first become Jews - i.e. become circumcised if male, observe the dietary laws, etc. - or if they did not, meaning in the latter view that the Christians would become a separate religion, not just another Jewish sect.
Well it's false when Paul tells us that 500 people at once had seen Jesus risen from the dead.
I probably should have qualified what I said. Let me do it now. I think Paul was being truthful regarding non-supernatural matters.
As to the 500+ brethren who supposedly saw the risen Christ at one time, there's evidence in the passage of later intrusive material being introduced. Here's the passage as we now have it (1 Cor. 4 - 8):
And that he [Jesus] was buried, and that he rose again on the third day according to the scriptures: And that he appeared to Cephas, then to the twelve. After that he appeared to more than five hundred brethren at one time, most of whom are alive today, though some have fallen asleep. After that, he appeared to James, then to all the apostles. Last of all, he appeared to me as to one untimely born.
Notice that the passage shows a widening circle of appearances up to a point, then sticks the appearance to James toward the end. It's reasonable that Paul would be at the end, since the passage an the material immediately following it is self deprecating. In Galatians it's apparent that James, not Peter, is in charge, which would hardly be the case if he was so far down in the order, and if Jesus first appeared to Peter. I suspect that sticking james at the end was done by a later editor to discredit him, while putting Cephas (Peter) in his place. After all, Cephas was one of the 12. I also suspect this editor threw in the 500+ brethren. Here is how I think (and this is only my speculation) the passage originally read:
And that he [Jesus] was buried, and that he rose again on the third day according to the scriptures: And that he appeared to James, then to the twelve. After that, he appeared to all the apostles. Last of all, he appeared to me as to one untimely born.
The fact that none of the gospel writers - who would reasonably have some knowledge of Paul and who were writing decades after he had written - mention the 500+ brethren means either they never heard of this, because the 500+ weren't in the original letter, or that the story might have been floating around, but wasn't considered reputable. It would be too stunning an evidence of the resurrection to leave out.
Paul does not need to be deliberately lying about anything. But it's surely obvious that he believed all sorts of things (religious things) that were untrue.
Agreed.
But whether or not Paul held false beliefs about God and Jesus, is not really the point here. The point is that there is nothing in any of his letters that is actually evidence of Jesus existing.
Again, agreed. As I've said, even accepting Jesus as historical, Paul dispenses with any real Jesus in favor of the Christ Jesus of the hallucinatory revelation of his conversion experience.
But if you think Jesus was more likely than not (I think you said that before?), then is that a conclusion that you have arrived at on the basis of some actual evidence of his existence? Or is that more like a gut feeling that Christians (eg pre-Paul) could not, or would not, have simply believed preachers of a mythical religious story?
The other dying and rising man-gods (such as Osiris and Dionysus) are usually killed by dismemberment, while Jesus is put to death by a known method of execution practiced in the area and possibly used by the Romans. For example, Josephus says that Alexander Jannaeus had about 800 Pharisees crucified. If the early Christians invented the story of the crucifixion,they evidently wanted to place Jesus in a historical setting. So, yes, they could have invented this. However, historicity it didn't seem all that important to other religions at that time.