Old testament accuracy of God's Word

Some of the old testament had to be written by word of mouth. the first 5 books of the old testament were written by Moses. Adam was created around 4000 B.C.E. Moses wrote Genesis in 1513 B.C.E. The other 4 books he was present for, but everything up to then he must have learned from word of mouth. Table of the Books of the Bible

The problem with the whole bible is that so much time has gone by that anyone could have changed the words of it. That could have been done on accident or on purpose during translation. For example the tetragrammaton YHWH, the name of god, was taken out of the bible due to superstitions of the Jews. This had to do with the 3rd commandment at Exodus 20:7. The Jews take on that was, "Well we will just take his name out and nobody can say it". That is clearly not what Jehovah god intended. Today sadly many bible translations are going that way. Just because we don't know the exact pronunciation doesn't mean we shouldn't try.

The old testament is still pretty accurate, more of the scriptures has come to light. Take for instance the dead sea scrolls of Isaiah. Ancient, untouched, unmodified documents that we can compare our translations to.

You also have to take into account that this is God's written word. Jehovah would never let anyone contaminate his word. In the Greek scriptures you find this verse at 2 Timothy 3:16,

"All Scripture is inspired of God and beneficial for teaching, for reproving, for setting things straight, for disciplining in righteousness, 17 so that the man of God may be fully competent, completely equipped for every good work."

Everything god put in the bible, he put there for our benefit. I would have to say that the old testament would be just as accurate as the new.

"Much of it spans generations, some of which was then rewritten by others and passed on by word of mouth."

Exactly how the text was transmitted is a subject of much debate. There's no concrete evidence that anything in the Bible was passed by word of mouth. There is some evidence that Old Testament manuscripts were edited or annotated after the original writing, for example substituting later place names for old place names. But that's little different from modern history books that include footnotes to explain obsolete place names, etc.

"Jews are only allowed to eat foods under specific dietary restrictions. ..."

Not clear how that is an argument against the accuracy of the OT. Jews and Christians have debated for millenia the purpose of the ritual laws. There's a popular theory that rules against eating pork are for health reasons. Maybe so. Maybe, as others have suggested, the purpose was to set the Jews apart from non-believers. Or that it was simply on the same order as rules about how to dress and holidays to celebrate: rituals intended to give people simple ways to act out their faith and to keep it on their minds.

"The old Testament follows much of the history of Israel, so at what point is it truly God's word versus man's?"

The Bible claims that God worked in a special way with Israel. That's why we call them the "Chosen People". Whether you believe this or not, given that premise it is not surprising that the history of how God worked with Israel would be a likely subject for God's word. Like, if you started a history book by saying that Britain showed a particular aptitude for science, it would not be surprising if the rest of the book concentrated on Britain and not, say, China.

"Did God talk to people directly, or as he does now, through an understanding of what must be done? I ask as if he did no talk directly to not only people in the bible, but those who wrote it, much of what was said could have the beliefs of those who he commanded intertwined in them, due to the free will God himself bestowed upon us."

The OT doesn't give all that many cases of God speaking directly to people if you add them up. Adam, Noah, Moses, Abraham, maybe a dozen or so prophets, spread over the course of several thousand years. Maybe God has spoken directly to a dozen or so people since the Bible was written. Or maybe we are supposed to rely on the Bible now rather than new revelations. Even if it is true that in the last 2000 years God has not acted in the way the Bible describes him as acting in the previous 2000 years, that hardly proves that the Bible is false. God could have any number of reasons for acting one way at one time and a different way at a different time. I haven't bought baby bottles or diapers for over ten years but did frequently before that. Is that mysterious? Not really: I no longer have small children.

"In cases the bible follows the life of a single person, whose history we do not know how the writer obtained, even if he had God's blessing to write it."

You could say that about many books. How does the author know the information he reports? Sometimes it's obvious: he claims to have been there or have talked to people who were or done research. But other times the author does not spell out how he knows. This tells us little about the reliability of what he writes. If someone doesn't tell us how he knows, he could just be making it all up. But if he claims to be an eyewitness, he could be lying -- either about being there or about what happened.