For about two decades John W. Loftus was a devout evangelical Christian, an ordained minister of the Church of Christ, and an ardent apologist for Christianity. With three degrees--in philosophy, theology, and philosophy of religion--he was adept at using rational argumentation to defend the faith. But over the years, doubts about the credibility of key Christian tenets began to creep into his thinking. By the late 1990s he experienced a full-blown crisis of faith. In…