Father Fortea, why is the devil called “The Accuser”?
“For the accuser of our brethren has been thrown down, who accuses them day and night before our God” (Revelation 12:10).
Every time we sin, Satan rejoices, and he never lets pass an opportunity for pointing out our offenses to God. In this 
sense, he “accuses” us before the Creator. Remember: when the devil wants to talk to God, he only has to direct himself to Him. God listens to everything the devil says to Him; He knows every thought that comes from a demon. This type of communication between God and Satan is reflected as much in the book of Job when they both speak as in the book of Zechariah (see Zechariah 3:1).
Satan’s only purpose here is to remind God of the many times he triumphs over us, i.e., the many times he is successful in tempting us to sin. After the Last Judgment, sin will no longer be possible and, as such, the devil will not be able to accuse us of anything.
Editor’s Note: To learn more about spiritual warfare and demonology, Catholic Spiritual Direction recommends Fr. Fortea’s excellent book Interview With An Exorcist – An Insider’s Look at the Devil, Demonic Possession, and the Path to Deliverance.
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Ar for this post on the devil being called “the accuser”: Gargoyles, Magdalen College, Oxford England, photographed by Chris Creagh, 27 July 2009 own work, CCA-SA 3.0 Unported; detail of Padre José Antonio Fortea 2017, photographed by Elgatoconbotaselgatoconbotas, 5 May 2017 own work, CCA-SA 4.0 International; both Wikimedia Commons. Cover of “Interview with an Exorcist” used with permission, all rights reserved. Wikimedia Commons.
