Disturbing to say the least
Let me start by saying this is cinematicallly beautiful. The colors, the camera angles, the use of real photography mixed in with the animation all pull together to create a grizly and dark atmosphere. I think the reason why so many people are panning you is because this piece is truely disturbing, and each bad review you should take as a complement.
That being said, there were a couple things that I didn't like. The priest's eyes didn't seem like they were attached to his head at times, like they were tweening at a different speed than the rest of his face. Another thing, when the priest's eye was stabbed out, there was just blood coming out. Eyes have not only blood but a clear liquidy stuff that should have been present. Same goes for the brain, there should have been some sort of yellow cerebral fluid dripping out (Yes, I'm just as demented as you are).
One last thing: I didn't catch why he said 'thank you' in the end. Did he feel somehow saved by all this? Is he going to continue to kill or did he get it all out of his system. That wasn't quite clear in the end.