This question is inspired by comments from this post:
https://christianity.stackexchange.com/a/92394/35508
In this question, I am referring to the Bible as the 66 books of the Old Testament and New Testament (as per the KJV).
For any religious text such as these two, when considering how or why that work came into existence, there is at least the explanation and account as presented in the text itself. If one is to reject the validity of that account, they would need to be able to present a plausible alternative explanation to explain how and why that work was created. At the least, this explanation would have to account for the motivations of the authors and any other witnesses who attest to the veracity of the message given. Additionally, it may have to account for any information included in that work which would otherwise not have been known to the authors.
How much of a stretch would any alternate theories have to go in order to be a plausible alternate explanation of each? Is there any consensus on which of the two works would have a more simple alternate explanation?
There are people who both believe and reject belief in both books, and there are many reasons one may do so. Furthermore, there may be good reasons to believe a work which otherwise has a plausible alternate explanation, and so this question does not address the believability of either account. This is only to examine the most simple alternate explanation for each.
Edit
First, I would like to thank those of you who have attempted an answer. However, from the responses, it seems that I would need to clarify that I am not asking about whether either account is actually true or supported by evidence. I am only interested in how plausible an alternative explanation could be for either work.
This would include things like describing least number of people would have to be involved in providing false or mistaken information. This may also involve whether or not there were any information included which could not have been readily obtained by the alleged author(s) apart from the proposed narrative.
It can be assumed that people in a time when they are writing a work would have information that is available to people in that time and place, regardless of whether or not they are telling the truth.
It might also be helpful to include potential motivations for why people might have attempted to create these works.