I'm of the opinion that perhaps early on there may have been some profanity but I would bet that after being in the presence of Jesus for a day or two, and seeing how holy He was, the profanities ended real soon.
I think Mel, devout catholic, needs to work on that. The references to ripping out the guys intestines and killing his dog is a bit much also.
Mr. Gibson was accurately reporting his emotions at the time...that was how he felt. If a Christian tells you he never feels negative emotions or urges, he's lying to you.
What is offputting is the graphic detail of Gibson's expression; but what's wrong with that? It may be shocking, but that primarily for its honesty.