I like the position you shot this from, however it appears as if the original was too dark and you tried to compensate in post. I think the basic editing rules really held this photo back.
Lovely interior shot of a cathedral with good depth and taken from a nice angle drawing the eye in. Good exposure with nice detail, color and lighting. It conveys the feeling of silence and also vastness very well. 8
Personally, churches and cathedrals don't elicit silence for me. There are still ambient noises I can hear in my mind. It's a good picture though. But the center doesn't seem sharp/in focus.
Great concept - no doubt that you have effectively conveyed silence. This idea has been done so well recently - see Best of 2008, so you may be marked down a bit. A little soft for my taste.