As an old, wise, and holy Franciscan priest once told me: “As an exorcist for 35 years (he was appointed an exorcist in South Africa), I can tell you Satan exists all right, for I have faced him; I have felt his presence; I have smelled him; I have heard him speak; and by the power of Jesus Christ and Holy Mother Church, I have driven his workers back into the pits of Hell. No modern theologian can explain this reality away.”
P.S. For more first hand accounts of dealing with Satan in exorcisms, read *An Exorcist Tells his Story *by Father Amorth, the Chief Exorcist of the Vatican.
In an interview with Fr. Amorth:
Interviewer: “You fight against the demon every day. What is Satan’s greatest success?”
Fr. Amorth: "To succeed in making people believe that he doesn’t exist. And in this he has almost succeeded. Even within the Church. We have a clergy and an episcopate who no longer believe in the devil, in exorcisms, in the extraordinary evil that the devil can cause, nor in the power that Jesus has given us to drive out demons.
For three centuries, the Latin Church - in contrast with the Orthodox Church and various Protestant confessions - has almost entirely abandoned the ministry of exorcism. As the clergy no longer practice exorcisms, as they no longer study them and have never seen them, they no longer believe in them. And nor do they believe in the devil either. We have entire episcopates who are hostile to exorcisms. There are countries in which there is not a single exorcist, as for example Germany, Switzerland, Spain and Portugal. A terrifying deficiency."
From:
fisheaters.com/amorth.html
