On a serious note, I am often presented with this problem by those on both ends of the belief spectrum, since it seems that as a moderate Episcopalian, I 'pick and choose' what I believe.
Nothing could be farther from the truth.
While I acknowledge how the Bible was assembled over the centuries, there ARE truths to be found in it.
Central to these truths is the teachings of Jesus.
But even these are written down stories from oral history
Still, I believe that there is a central tenet that He very likely said: Love God with your whole heart and love your neighbors as yourselves. From these the rest of the Law derives.
And thus has been the test I use when looking at Bible and deciding what to follow.
(For example, it is why I am in support of Gay marriage even when the old testament and Paul speak out against homosexuality.)