Sullivan, an Episcopal turned Evangelical turned agnostic had this to say about Christianity:
Everything about Christianity can be justified within the context of Christian belief. That is, if you accept its terms. Once you do, your belief starts modifying the data (in ways that are themselves defensible), until eventually the data begin to reinforce itself…
This is why you can never reason true Christians out of the faith….it’s that faith is a logical door that locks behind you. What looks like a line of thought is steadily warping into a circle, one that closes with you inside.
Sullivan succinctly details why Christians believe things that, from the outside, are viewed as irrational, bat-shit crazy beliefs.
A Christian must first embrace the belief that the Bible is truth, that it has supernatural qualities, a message from an infinite God to his finite creation. Once the Bible is embraced as truth everything can then be judged by that truth.
The Bible becomes self-attesting.The Bible is true because it says it is true. Until a person sees or even dares to contemplate that the Bible may not be what Christians say it is, it is quite impossible to have a meaningful discussion with a Christian. They believe because they believe.
This doesn’t mean we shouldn’t continue to engage Christians on rational, evidence-based grounds, but we should be cognizant of the fact that they will not likely be won over by evidence alone.
While my deconversion ended with a rational, open reevaluation of the Bible and the central claims of Christianity, it began with my disaffection with the Christian church. Most deconversions, I suspect, are a mixture of emotional responses and intellectual pursuits.