St Thomas Becket (Tevington submission to Catholic 365)
1673 When the Church asks publicly and authoritatively in the name of Jesus Christ that a person or object be protected against the power of the Evil One and withdrawn from his dominion, it is called exorcism. Jesus performed exorcisms and from Him the Church has received the power and office of exorcizing. In a simple form, exorcism is performed at the celebration of Baptism. The solemn exorcism, called "a major exorcism," can be performed only by a priest and with the permission of the bishop. The priest must proceed with prudence, strictly observing the rules established by the Church. Exorcism is directed at the expulsion of demons or to the liberation from demonic possession through the spiritual authority which Jesus entrusted to his Church. Illness, especially psychological illness, is a very different matter; treating this is the concern of medical science. Therefore, before an exorcism is performed, it is important to ascertain that one is dealing with the presence of the Evil One, and not an illness.
In the early 1970s, far more significant than the Exorcist (for anyone truly paying attention) would have been the words of St Pope Paul VI:
This matter of the Devil and of the influence he can exert...is a very important chapter of Catholic doctrine which should be studied again, although it is given little attention today....
The Christian...must at times make use of special ascetical practices to escape from certain diabolical attacks. Jesus teaches us this by pointing to "prayer and fasting" as the remedy.[29] And the Apostle suggests the main line we should follow: "Be not overcome by evil, but overcome evil with good. "[30]?
With an awareness, therefore, of the opposition that individual souls, the Church and the world must face at the present time, we will try to give both meaning and, effectiveness to the familiar invocation in our principal prayer: "Our Father . . . deliver us from evil!" (11/15/1972)
Conclusion