two movies i think

first--a nun walking up to the altar in a church and stops and looks to the left and turns into a demon???

second-- scene in an old church where Jesus starts to pull free from the cross??

might be the same movie.

i started watching it in a dark room at like 2:00 am and decided i would finish it later, never finished it

any ideas???
thanks

Demon Hunter?

http://www.imdb.com/title/tt0435631/?ref_=sr_2

Depending on how old the movie looked, it could be a number of films. The first movie that popped in my head was The Convent from 2000. There's a scene similar to what you described in the clip below

http://www.youtube.com/watch?v=klWVq47u8kA

The trailer:

http://youtu.be/UiqdigykKm0