When we merely say that we are bad, the ‘wrath’ of God seems a barbarous doctrine; as soon as we perceive our badness, it appears inevitable, a mere corollary from God’s goodness. To keep ever before us the insight derived from such a moment [of perceiving one’s own sin], to learn to detect the same real inexcusable corruption under more and more of its complex disguises, is therefore indispensable to a real understanding of the Christian faith. This is not, of course, a new doctrine. I am attempting nothing very splendid…. I am merely trying to get my reader (and, still more, myself) over a pons asinorum—to take the first step out of fools' paradise and utter illusion.
As Lewis says, this insight really is indispensable to a real understanding of the Christian faith. I’m more convinced of this every day. I also suspect, sadly, that many Christians never take the first step out of fool’s paradise and utter illusion. Maturity in the Christian life consists, in great measure, in progressively realizing how deep the rabbit hole of one’s own sin goes. Spiritual growth is not always, or even often, particularly glamorous. Lewis is spot on: It’s often detecting corruption under layers of rationalization, buried even from one’s own self by “complex disguises.” To unmask and uncover all this, painful and humbling though it may be, is the Christian path to joy and freedom.