Your question raises a number of issues that are clearly strong points of contention in American society today. I'll outline several that I see.
First of all, your question asks about the Bible, but your expansion refers to the beliefs of Jesus, narrowing the focus to the New Testament, excluding the Hebrew Bible (which Christians often call the Old Testament).
Each must be treated separately, as the issues are different, although they overlap. I'll discuss with the New Testament only here.
There are Christians who believe that the Bible we have (or at least it's Greek version) are the Word of God exactly as God wants it to be, free of errors. This is called Biblical Inerrancy, stating the Bible is free of errors, making historical analysis irrelevant.
There are those Christians who believe that the common sense meaning of the Bible is obvious to so that no interpretation is necessary & that what they are doing is not interpretation, but Biblical truth. This is called Biblical Inerrancy.
If both of these are believed & extended to current translations, then the view is that the present New Testament reflects the truths revealed to Jesus by God.
The above are religious positions about truth, and do not address either issues of history or issues of understanding or interpretation (society, culture & psychology).
If we take a historical & interpretive view, these questions arise:
- Are even our original texts accurate to what Jesus revealed from God? Did anyone understand Jesus when he spoke? Peter denied him and later repented. Paul never met him and persecuted Christians. Perhaps no one understood Jesus well at the time, and that ongoing Christian life actually means that we can understand Christ's teaching better now? This is the idea of ongoing or progressive revelation.
- The text that were put together from oral tradition (redacted) may not be accurate.
- The texts that were accepted as the correct ones, and the others that were rejected, may have been done on a political basis, or done accurately (canonization), and even today there are multiple canons.
- Later ideas or ideas Jesus did not believe but his audience did could have been added, especially about hell.
- Some of the letters show evidence of being written later and ascribed to earlier apostles (pseudo-Pauline and pseudo-Petrine letters, and the belief that the John of Revelation is associated with the John of the Gospel.)
- After all of this, issues of translation come in