The Malleus Maleficarum by Kramer and Sprenger, 1489, Excerpts
There are still some means by which these devils may be driven away, five ways by which girls or men can be delivered: first, by Sacramental Confession; second, by the Sacred Sign of the Cross, or by the recital of the Angelic Salutation; third, by the use of exorcisms; fourth, by moving to another place; and fifth, by means of excommunication prudently employed by holy men.
In the exorcism of one who is bewitched; he should first have made a good confession, and if possible he is to hold a lighted candle, and receive the Holy Communion; and instead of putting on a chrisom, he is to remain bound naked to a Holy Candle of the length of Christ's body or of the Cross. And then may be said the following:
“I exorcise thee, Peter, or thee, Barbara, being weak but reborn in Holy Baptism, by the living God, by the true God, by God Who redeemed thee with His Precious Blood, that thou mayest be exorcised, that all the illusions and wickedness of the devil's deceits may depart and flee from thee together with every unclean spirit, adjured by Him Who will come to judge both the quick and the dead, and who will purge the earth with fire. Amen.”
And let the exorcist continually sprinkle him with Holy Water. And note that this method is recommended, not because it must be rigidly observed, or that other exorcisms are not of greater efficacy, but that there should be some regular system of exorcism and adjuration. And this sort of exorcism may be continued at least three times a week, that so through many intercessions the grace of health may be obtained.
When the exorcist is not ordained to the Order of Exorcist, then he may proceed with prayers
But if anyone asks what is the difference between the aspersion of Holy Water and exorcism, since both are ordained against the plagues of the devil, the answer is supplied by S. Thomas, who says: The devil attacks us from without and from within. Therefore Holy Water is ordained against his attacks from without; but exorcism against those from within.
But in exorcising a bewitched person both methods are to be used, because he is tormented both within and without.
Exorcist Convention: Priests Learn How to Fight the Devil
14 Nov 2010
More than 100 Catholic bishops and priests gathered in
Baltimore this weekend for a two-day conference on exorcism, organized by a bishop who said he wants dioceses to be prepared. U.S.
Chief exorcist says Devil is in Vatican
11 Mar 2010
"The Devil resides in the Vatican and you can see the consequences," said Father Amorth, 85, who has been the Holy See's chief exorcist for 25 years. The recent revelations of "violence and paedophilia" committed by Catholic priests against children in their care was also the work of the Devil, said Father Amorth, who is the president of the Association of Exorcists, has previously claimed that both Hitler and Stalin were possessed by the Devil. He also condemned the Harry Potter books, saying they were dangerous because they dabbled in the occult and failed to draw a clear distinction between "the Satanic art" of black magic and benevolent white magic.
President of Honor of the Association of Exorcists.