“You’re right, I was mistaken in saying that” or “you have a good point there” aren’t phrases you’ll often hear from a religious apologist. It can be frustrating in a debate when none of your points seem to get across. Why is this? I shall examine some of the reasons why you’ll never get through to an apologist.
1. Relentless Bias
In order to get someone to change their mind, they have to actually be open to changing it. One of the most revered apologists out there William Lane Craig demonstrates closed mindedness in it’s extreme very well:
Mark Smith (of http://www.jcnot4me.com) set up the following scenario for Craig: “Dr. Craig, for the sake of argument let’s pretend that a time machine gets built. You travel back to the day before Easter, 33 AD. We park it outside the tomb of Jesus. We wait. Easter morning rolls around, and nothing happens. We continue to wait. After several weeks of waiting, still nothing happens. There is no resurrection–Jesus is quietly rotting away in the tomb”
Smith asked Craig, given this scenario, if he would then give up Christianity, having seen with his own two eyes that Jesus did not rise from the dead. Smith wrote “His answer was shocking, and quite unexpected. He told me face to face that he would STILL believe in Jesus, he would STILL believe in the resurrection, and he would STILL remain a Christian. When asked, in light of his being a personal eyewitness to the fact that there WAS no resurrection, he replied that due to the witness of the ‘holy spirit’ within him, he would assume a trick of some sort had been played on him while watching Jesus’ tomb. This self-induced blindness astounded me.” If anyone doubts what Craig said in response, Mark challenges him or her to ask him the same question 
Craig admits that there is nothing you could ever do to get him to change his mind. Even if you did build a time machine, and show him that Jesus did not rise from the dead! I agree with Smith when he states that this level of closed-mindedness is astounding. Here you have a man who enters into debates, without a hint of open mindedness. He freely admits that you could do nothing to change his mind.
This kind of closed mindedness, a complete unwillingness to concede that their position might be wrong, no matter what you might show them is the first major reason why you’ll never get through to an apologist.
2. The ‘I Can’t Claim To Know The Mind of God’ Card
This is the ultimate get out clause for the apologist. When faced with a tough question or challenge they will respond by saying ‘I can’t claim to know the mind of God’ or words to that effect. Again Craig provides a nice example of this on his website:
So when people ask, “Why doesn’t God just remove all the suffering from the world?”, they really have no idea what they’re asking for or what the consequences might be. The brutal murder of an innocent man or a child’s dying of leukemia could send a ripple effect through history so that God’s reason for permitting it might not emerge until centuries later or perhaps in another country. Only an omniscient mind could grasp the complexities of directing a world of free persons toward one’s pre-visioned goals. You have only to think of the innumerable, incalculable contingencies involved in arriving at a single historical event, say, the Allied victory at D-day, in order to appreciate the point. We have no idea of the natural and moral evils that might be involved in order for God to arrange the circumstances and free agents in them necessary for some intended purpose, nor can we discern what reasons God might have in mind for permitting some instance of suffering to enter our lives. But He will have good reasons in light of the purposes of His Kingdom. 
What Craig is essentially saying here is we can’t possibly comprehend the mind of God, or the plan that he has in store for us. This absolves him of the duty of explaining the problem of suffering. He can just say ‘I don’t understand why God allows it, only God understands that’ and can dodge the bullet conveniently.
The problem with this is that the apologist only plays this card when necessary. They have no problem understanding the mind of God when it comes to most aspects of their theology, such as the nature of God (‘God is loving’ etc) the fact that God is the God of the Bible, that God is a ‘he’ and so on. Clearly the apologist makes claims to understand the nature of God when it suits them, and when it doesn’t they will dodge the issue by claiming ignorance.
3. The ‘Reductionist’ Card
If I was to provide compelling evidence to show that, for example, religious experiences originate in the brain, an apologist would immediately dismiss this as being ‘reductionist’. In their eyes I would necessarily be leaving out a key ingredient in the process (namely God) – so they would never accept such explanations no matter how compelling. The thing is, such explanations are not reductionist, unless you can show that there is something that they are leaving out. If I was to argue that tea had a special magic ingredient, I couldn’t call you a ‘reductionist’ for explaining it as being simply dried out tea leaves and hot water. It’s up to me to show that there really is a magic ingredient before I start accusing you of missing something out.
Similarly, if I explain religious experience, and how it originates in the brain – you can’t go calling it reductionist until you show me that I am actually missing something out of the explanation.
4. Shifting the Burden of Proof
If I was to say that there was a magic ingredient in tea, would I be justified in challenging someone to prove that there isn’t? No. The burden of proof lies on the person making the claim. Similarly if you claim that God exists – the burden of proof is resolutely on you. I do not have to prove that God does not exist. The amount of times I have seen people trying to shift the burden of proof is astonishing.
5. Personal Experience Trumps All
This is related to the first section of the article. Perhaps the most common apologist tactic is to appeal to personal experience ‘I just know God exists, and nothing you could show me could change that.’ – The thing is personal experience is completely unreliable, and should not form the basis of belief at all. Plenty of people have convincing personal experiences of voices telling them to do things, and other such delusions.
A short walk through the ward at a mental hospital will show you with great clarity that personal experience is not reliable. This does not stop the apologist from relying upon it in discussions however. Craig calls it the ‘Self-Authenticating Witness of the Holy Spirit’ and it’s his ultimate trump card. You could demolish all of William Lane Craig’s arguments and even take him back in a time machine and he would always find ways to wriggle out of admitting he’s wrong because he knows he’s right.
Apologists are masters of the art of keeping the doors in their mind’s firmly closed, using the tactics mentioned in this article and others to refrain from ever admitting defeat, or even the possibility of being wrong. The religious apologist is merely an apologist for their own closed mindedness and bias.
 Loftus, John W. – Why I Became An Atheist page 214