Because man little admits, little recognizes, the true condition of his heart. The chains of his bondage and the shackles of his slavery have become so commonplace, so ‘normal,’ that they are no longer seen.
The passions have become such familiar and commonplace enemies that man loses sight of their true character, their oppressive nature, and even starts to consider them friends.
The enemy which ceaselessly wages war against him is so much a ‘part of the fabric’ that he ceases to be seen at all; his existence begins even to be denied. So the spiritual struggle becomes a non-struggle, which makes it a defeat; for if we don not recognize our state, we cease to rise to the contest in full seriousness and vigor- and then our passions reign , sin triumphs, and devil stakes a firmer claim.
Fr. Irenei, The Beginnings of a Life of Prayer