Sinners cannot cast out devils.
         Acts 19:14-16, And there were seven sons of one Sceva, a Jew, and chief of the priests, which did so. And the evil spirit answered and said, Jesus I know, and Paul I know; but who are ye?
And the man in whom the evil spirit was leaped on them, and overcame them, and prevailed against them, so that they fled out of that house naked and wounded.
         
          If sinners could exorcise evil spirits it would be a house divided against itself.
                    Matthew 12:26-27,  And if Satan cast out Satan, he is divided against himself; how shall then his kingdom stand?
²⁷ And if I by Beelzebub cast out devils, by whom do your children cast them out? therefore they shall be your judges.