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We have a strange illusion that mere time cancels sin. I have heard others, and I have heard myself, recounting cruelties and falsehoods committed in boyhood as if they were no concern of the present speaker's, and even with laughter. But mere time does nothing either to the fact or to the guilt of a sin. The guilt is washed out not by time but by repentance and the blood of Christ: if we have repented these early sins we should remember the price of our forgiveness and be humble.

C. S. Lewis (2003). “A Mind Awake: An Anthology of C. S. Lewis”, p.105, Houghton Mifflin Harcourt
We have a strange illusion that mere time cancels sin. I have heard others, and I have heard myself, recounting cruelties and falsehoods committed in boyhood as if they were no concern of the present speaker's, and even