Jesus was an orator and not a writer. Those people who were effected by his words wrote down as many of his wisdom filled sayings and parables as they could remember. It is possible the earliest bible was just a sayings book and there is historic evidence to support this idea. Although it was more than 200 years ago, Thomas Jefferson worked to attempt to separate the sayings from the story. Why would he do this unless he believed it might have been possible that it began as a sayings book? Perhaps the sayings stand on their own?