Believers fail to realized that they know little about religion. It's like being in a forest. You can learn all about the trees in that forest there, but you have to get out of it to learn about forests. If you stay in a particular religion, you have no rational postulates, just 'divine' dictums, and almost all debate involves circular arguments, and when that fails they just say that 'faith' is the final answer to every question, but it's really just another baseless postulate.