St John Cassian explains: “All other vices dwindle as we overcome them, and day by day become weaker in defeat…But [vainglory] rises again from defeat more eager for the fight, and when you think it is extinct, it recovers from its death all the more lively. Other types of vice normally only attack those whom they might defeat, whereas this one presses hardest on its conquerors. The more successfully we elude it, the harder it assaults us through our very joy in victory.”
Thus, vainglory “is far more dangerously deceptive to the unwary warrior.” Whoever undertakes the therapy of vainglory, then, will have to employ great spiritual discernment and constant watchfulness from start to finish.
~Dr Jean-Claude Larchet (Therapy of Spiritual Illnesses vol.3, p.117)