CathInfo.com

The Holy Ghost can be very helpful, and quick.  I have had about 3 experiences where demons show themselves in people.  This last one was a man, I have known for 25 years.  He needs prayers.  He left his family of many children and wife.  I don't know and don't need to, but I saw him in the church's parking lot. I stopped my car and put the window down.  He didn't much to say, and we were on the subject of being forgetful.  I said, well that's for me to do, after all I am 20 years older than you.  He made a reply and I said, well, ask the Holy Ghost and the next thing I knew, I had a swarm of flies at my face and I just kept swatting and I couldn't take it anymore and put my window up saying goodbye, see my husband inside the church.

I understand flies can appear with priest who come to exorcise.  It was so strange.  Another time, a man looked at me with disgust, and I just left my pew for another. 

But remember to say things that are used in exorcism "Jesus Christ, Mary, but demons hate the "Precious Blood" very much.