Here's why I think the God of the Bible doesn't exist. And I'll just focus on one thing. The mythicist position.
The Bible is based off of older mythologies. For instance, and I get this from Tim Callahan's book Secret Origins of the Bible, the Israelites started off as pagans. According to Callahan, the ancient Israelites believed in many of the same gods as the Egyptians and the Canaanites.But as time went on, the mythologies conglomerated and began to be reinterpreted.
We forget that the writing of the Bible spans approximately 1600 years. The Israelites were never a great nation, though they make claims to that in the Bible. It is exactly this reason (that the Bible was written over 1600 years), that there are so many contradictions and inaccuracies in the Bible. Now, people may object to this claim but any reader would see that it takes a certain amount of mental gymnastics and semantic hoop-jumping to make it seem like the Bible isn't contradictory or inaccurate.
But really, it's the story of a cultural transition, from ancient pagan traditions borrowed from neighboring cultures to the consolidation of those into one God. El Elyon, translated as "Most High God", for example, was used by "Melchizedek (above left), the Canaanite priest-king of Salem who sacrificed to him on Abraham's behalf. Christian apologists say that Melchizedek sacrificed to god of the Jews, however that can not be true because "El Elyon" was a god worshipped by the Canaanites. Apparently, apologists later just said El Elyon was a reference to Yahweh.
El (pictured at right) was a sky god, creator and the grey-bearded patriarch of the Canaanite gods." (from Tim Callahan's Secret Origins of the Bible). You know the archaic image we all have of the bearded man in the clouds? That is El.
But it's not just the Old Testament that is full of ancient mythology, the story of Jesus himself is reminiscent of ancient gods, mirroring elements of stories like Osiris-Dionysus, and others.
The point of my argument is this:
1. Christians base their worldview on the Bible, claiming that the Bible is the inerrant Word of God.
2. Almost all Bible stories, but especially Old Testament ones like the Fall of Man and the Flood Myth are derived from the mythology of surrounding cultures at the time.
3. The New Testament needs these older myths to make sense out of Jesus Christ's death, because the Son of God died for the sins of mankind, who were cursed to be in a sinful state since the Fall of Man.
4. So, the Christian worldview has its foundations built upon old myths.