There is a vast difference between the
authenticity of works supposedly
inspired by God, and those that are said to be the
actual words of God
verbatim. Many different religious text claim to contain the words of God but only a few (eg the
Quran) claim to be totally and completely Gods word without any
alteration,
addition,
editing,
deletion, or any other form of change. Also to validate that something is indeed
divine and not simply the figment of
human imagination and
longing once must examine it's historical context, eg previous
translations, and
revisions throughout
history, if these are
identical or at least
consistent, it goes a long way to allaying the fears that the "Word of God" myth is indeed a
myth.
For all the scepticism, if any of these books do contain the actual word of God it is likely not to be immediately popular as it will ask for radical personal changes.