It is a fact that anybody could live somewhere, for example Palestine, for a year or a decade, and then at any later time encounter a reason to make up stories about events set there. That is the origin story of probably tens of thousands of novels, good and bad. I could recommend a few.
Thus, it strikes me as very weird to object to such a historical possibility (except on theological grounds, which are out of scope here).
You could reasonably object that the evidence would better place the origin of the cult in some other Roman city, such as Antioch or Alexandria, and I know of no evidentiary reason to prefer one over another. Romans did get around.
> It is a fact that anybody could live somewhere, for example Palestine, for a year or a decade, and then at any later time encounter a reason to make up stories about events set there.
Right, but we don't have just a single book by a single person. We have five books by four people, as well as loads of letters. Are you saying a single person from this cult made up this story, and then wrote it four different times? Are you saying four different people from this cult had all lived in Palestine, and decided to tell the same story four different ways? Are you saying one person made up the story and wrote it down, and three other guys came along and did their own version of it, but somehow managed to be accurate about names and places in spite of not having lived there?
None of these things are impossible; but in the absence of some actual evidence for this, they certainly seem less probable.
> Thus, it strikes me as very weird to object to such a historical possibility (except on theological grounds, which are out of scope here).
OK, so according to Wikipedia, the earliest copy of Luke that we have is titled, "The Gospel according to Luke"; dozens of references from early Christians refer to Luke as its author; and no source ever refers to the author as anyone else. But to you this is "no evidence that Luke existed".
But so far the only arguments you've made for your cult-retrofitted-exotic-backstory theory are "it could have happened".
I'm not the one judging theories differently based on my theological preferences.
One individual with direct experience of life in Palestine -- say, Paul -- suffices to write down a story with geographical details. As many people as you like may then crib from such a story. But we do know of more than one person who had lived in Palestine, in the period.
I do not judge theories. Historians judge, and report their results. As I understand the scenario, the theology came first, then the parables, then a person to quote parables from, and finally biographical accounts of that person's life, all unfolding over decades according to the needs of an expanding church.
I do not find anything implausible in their results, or in their reasoning. You are welcome to your own conclusions. If you have a problem with historians' results, you may take it up with them.
Thus, it strikes me as very weird to object to such a historical possibility (except on theological grounds, which are out of scope here).
You could reasonably object that the evidence would better place the origin of the cult in some other Roman city, such as Antioch or Alexandria, and I know of no evidentiary reason to prefer one over another. Romans did get around.