Snark, I realize you’ve taken a month off, but I figured I’d reply now anyway:
(1) On Lucifer: thanks for the clarification. To non-LDS Christians, there’s a distinct difference between the Bible and the BoM.
(2) On evidence for BCE Christianity in Eurasia: the Biblical scriptures count as historical evidence in a way that the BoM doesn’t. The most ancient copies we have of the BoM date from the early 19th century. While it may describe events that it claims happened at or before the time of Christ, it neither dates from the period described, nor does it represent a link in a chain of continuous transmission of the information contained in the BoM.
In contrast, the earliest extant copies of the New Testament date back to within a few centuries of the time they describe, and documents of the intervening period enable us to verify the existence of various NT books at dates well before the dates of our copies.
And while the Masoretic Text of the OT is largely from the 9th century AD, the Septuagint and the Dead Sea Scrolls corroborate the earlier existence of the OT, as do references to parts of the OT in other sources from antiquity. And there are historical reasons to presume that much of the OT was passed down in oral form for some time before being committed to writing.
Hence the Bible is evidence in a manner that the BoM is not. That doesn’t mean historians should take it literally, and most don’t: for instance, many historians are skeptical as to whether the Hebrews were ever in Egypt, or whether the kingdoms of David and Solomon were anywhere near as substantial as the Bible suggests.
So this is what I mean. There is evidence that the faith we now call Judaism was practiced for centuries before Christ. There is evidence that Christianity was practiced from the middle of the first century AD until now. But there is no evidence of BCE Christianity either existing or influencing Mithraism, period.
This is not dumping on your faith; that you believe in the divine origins of the BoM is fine with me, and seems to work for you. But that’s belief, not evidence - except to another Mormon. Just as the Bible is evidence of the bodily resurection of Christ only to another Christian.