The Judeo-Christian religions were the first to hit upon the idea that their holy books are true because god says they are, we know this because the holy book is the word of god and the word of god tells us that god does not lie when he tells us the religion is true as expressed in the holy book, which is the word of god proving that god exists and so on and so on for ever and ever amen.

if one link is broken in this chain the whole thing falls apart, therefore even the most stupid idiotic ideas MUST be retained and excused no matter how immoral or evil they might be.

We actually DO know that they were.

Exactly!

If so, god was extremely stupid with his own creation.

Welcome to the forum.

I see it as the efforts of Jewish leaders to maintain the identity of the people which was in real danger of disappearing while they were in exile in Babylon. This was happening around the 6th century BC. They used the myths common to the people around them and applied them to themselves in particular.

It seems every people wanting to become a unified entity do this. One of the myth-making books in my own country is the Book of Invasions and the comment about it below could apply everywhere:

Purporting to be a history of Ireland and the Irish, a critical analysis by Thomas F. O'Rahilly claims the purpose of Lebor Gabála Érenn (Book of Invasions) was three-fold:

... firstly to unite the population by obliterating the memory of previous and different ethnic groups, secondly to weaken the influence of pre-Christian pagan religions by converting their gods into mere mortals, and thirdly to manufacture pedigrees into which the various dynastic groups could conveniently be fitted
[en.wikipedia.org]