“For sorcery to work one must give the devil rights over oneself. In other words one must provide some serious occasion and be personally unprepared through repentance and Confession. One who goes regularly to Confession is immune to sorcery even if it’s piled on him by the shovelful. For when someone has confessed and his heart is pure the sorcerers cannot cooperate with the devil to do him harm.”
Elder Paisios
~Spiritual Struggle