The religion of Christians was part mystery school of Serapis part gnostic and possible part Jewish Greek made up Torah. I think it was Pliny that wrote to his Caesar about what todo with this wierd group he had encountered while governor of a part of Turkey. He had held higher positions throughout the empire even in Rome yet never heard of a Christian before. The Bible only became a thing in response to writings by Marcion. Then when Constantine embraced the religion the writings of the Bible really started to be put together and formulated.
What most people don’t know is that the cannon was changed and changed and changed again many times for many more centuries. Then the Protestant reformation happened and it was dramatically changed again.
Also what most people don’t realize is the oldest bible writings in many places its unreadable. Of the four major codexes scriptures like 1or 2 Timothy 3:16 where we see it say that the Bible is inspired , it’s unintelligible. All over the New Testament the name for Jesus in Greek many times is just one letter like a I or a O.
Bart Erhman wrote that many of the scribes would make notes about what they thought the text may of ment or said and then later these notes became part of the actual bible.