The Mysteries of Genesis

I've been reading along in Genesis and truly trying to look at the authors along with the actual words used in the text. However, the story can be so "out there" at times that I c0mpletely forget to think about who the author could have been and I focus on figuring out how a text that is supposed to be used for righteousness can have so many crazy characters and experiences. Like for instance when the two girls sleep with their father, dang I wish I had my book with me right now, but it's in like Genisis 20 or 21. Dude, NASTY!!!!!! I understand that in the story of the bible, for man to produce and there to be so many humans on earth, that people were, well, "hooking up" with their blood relatives in order to do so, but when there's already a world full of people there is no excuse for sleeping with one's father. I almost slammed the bible down then and thought about dropping the class. I know we are supposed to be reading the bible as a text for literary purposes, imagery, and all that, but it's hard to let my faith go. This story shook my faith. Then to make things worse, the fact that Abraham gets to lie to people all the time, the man is kind of a screw up, although a God-fearing screw up, and he gets away with it. I always thought stories had a rhyme or reason to them. A meaning that, as a reader, would be seen and understood. I do NOT get why Abraham is in such good faith with God when he lies and is almost moronic acting. The story of the two girls and their father, were obviously a need to have in this text, but why? I mean really, why? Is it to show what not to do to disgrace God or is it some sick twisted story for some other purpose? Right now I'm in such shock from reading all this that I'm not sure I ever want to read anymore ever again. I find it interesting though, how the Old testament is so different from the New Testament. The New Testament shows a loving, caring God who shows the reader what lesson is supposed to be learned, but in the Old Testament, it's like God is jealous and vengeful. The Old Testament has stories that are hard to understand because there seems, to me, to be no reason for them. Nothing ever really gets explained. However, the words used to write these stories illustrate, in my mind, the perfect setting for all of them to take place. Right now, I'm not sure how I feel about this text.