Stagefright - who me?

     How is it that I can be completely at ease with my classmates discussing Socrates and other deep thinkers, calmly lead the class in a trivia game that focuses on our five books we studied together, but change the subject to my faith and suddenly I have a case of the nerves? I just don't get it. I have plenty of public speaking experience. I have shared my faith with them from the beginning of the semester. I don't start out that way in my presentation but suddenly I find my voice a bit shaky, palms sweaty and hands start to shake. I have no reason for it. I was less nervous completing the challenge for the presentation than telling them about it. 
      I like my classmates, I trust them, and I can discuss deep, difficult topics easily with them. I noticed it's whenever my faith comes up and I'm leading discussion that I get the jitters. It doesn't make sense. I have been leading classes at church for years although I managed to do it alone or with an helper - no pressure there. It's almost a subliminal fear. I don't even feel a hint of fear before or even in the beginning.

     For my presentation, I chose to challenge myself to teach the kids at church with a mentor present and ask for an evaluation. I measured my success on if I went through with it, if the kids learned, and if the mentor said I did a good job. I completed it and was excited to share with my class at school. Here I am telling them about it and all my fears crept up on me again. To try to stifle the jitters halfway through my presentation, I told the group that even thinking about my challenge was making me nervous. I mentioned it later to a classmate, but she said it was a good presentation.

So how do I combat this new subliminal fear that's trying to scare me out of talking about my faith? Is this one of those strongholds that the devil is putting on me because I'm getting braver in sharing?