One major difference between a wise man and a fool is their ability to question their own beliefs. In the world today, too many people are keen to express their beliefs, but not so keen to hear others. I've even seen one woman who, upon being kindly offered a tract, proceeded to strike the pack out of the witness's hands, and refused to allow him to pick them back up.
Speaking as a Christian, I am confident enough in my views to allow them to be questioned, as well as to actively question them myself. In fact, I frequently play Devil's Advocate with myself, imagining I am about to apostatise and considering reasons I might do this. This not only allows me to reinforce my own faith, but also to develop techniques that enable me to share that faith with open and reasonable minds. This is the entire point of discussion. In my mind, if Christianity is not true, I don't want to believe it. If it is true, I don't just want to believe it myself, I also want to know why I believe it, and then give those reasons to other people so they, too, can believe.
This actually extends far beyond just Christianity. Realistically, it is impossible to question every belief you hold. But it is almost inevitable that some of the views you hold, you just take for granted. For example, I believe the Earth is a sphere, which orbits around the sun. However, other people believe the Earth is flat, and that the sun orbits it.
Most of us know the Earth is round, but how many of us can rationally defend that belief? Having spoken to flat earthers, it is my experience that they are actually pretty good debaters. I still believe they are embarrassingly wrong, but I have far more respect for them than someone who clings to "consensus" as a fail safe (Evolutionists, I'm talking to you). By contrast, round earthers do tend to cling to consensus science as an argument. That, and "there are photos", is pretty much all they can say in defence. Both of these are fallacious. Appeal to authority and appeal to populas are both logical fallacies, and there are photos of a 12ft t-rex attacking a car.
The shape of the earth isn't exactly critical. If you believe the earth is flat, the worst that's going to happen is you'll sink your social life. But religion is a lot more important. Therefore, it is beyond vital to question your religion. Those who do not question their religions betray inherent doubts about it. Even Christians who are afraid to question their faith because, as one girl said to me, they're afraid they won't know how to answer the tougher questions, need to consider that those who confront them don't care. It's like refusing to learn self defence techniques because you're afraid of fighting. You're going to get hurt.
Thus, there are only two wise options: Question your religion and find out it's wrong, then get rid of it, or, for Christians, question your religion, find out you were correct, and learn how to show that to others. If you really believe your religion is true, questioning it should absolutely never be a problem for you.