When arguing with religious, one runs into many interesting aspects of the human character.  Close to the top of the list is Confirmation Bias – or the idea that we tend to cultivate and seek out views and standpoints that we agree, often at the expense of the truth of the matter.

Qualia Soup illustrates the process with religious arguments he’s faced in the past.

The challenge we all face is being charitable and arguing with what people have said/are saying, not what we think they are saying.  (Easy to say, hard to do, especially in the heat of the moment.)