"First Springfield Church: "Where Every Sunday is Super Sunday!--sign outside The Simpsons' Church

Here are the facts:

I have studied, and feel comfortable with my level of knowledge of my subject matter.

I'll be following 25 minutes of Christmas music, so everyone will be in a good mood.

The listeners, as far as I can discern, like and love me. Generally speaking, they haven't communicated anything to the contrary.

I've done this about 10 times before in the same environment. Literally a thousand times in other environments.

It's only going to last between 30 and 45 minutes. Frankly, I could do 30 or 45 minutes on this topic without much preparation.

Here's the subjective reality:

It feels as if the cast of the off-broadway show "Stomp" are doing their final number in the pit of my stomach. I have little idea why this is the case.