I'm an atheist, but I thought one of the main reasons to read the bible was not to just read a story, but rather to understand God's message? For example, in the Old Testament, if you take the story of Abraham and Isaac at face value, God seems like a total dick! He tests a true believer's faith to the breaking point and when he realizes that yes, his true faith is the real deal, God says "haha just a test, nevermind!"
But the meaning behind the story is one of faith and attempting to understand God's mind. Questions of doubt and faith and love and family come into play. From looking at the text on Amazon, it looks like this has been mostly glossed over in an attempt to be witty. For example, the section on Genesis says "God's one rule was that they couldn't eat from this magical tree he'd planted in the center of the garden. I don't know why he put it there. It just tied the whole garden together."
So, not only is it dismissive of the meaning behind the tree of knowledge of good and evil, but it throws in a Big Lebowski reference.