Think about your relationship to your own history.  You could reject that history entirely.  You would embrace a principle of radical discontinuity.  Or you could embrace that history entirely.  You would reject any discontinuity at all.

If you refuse to change at all, you are rejecting being alive.  Life is an arrow in time, which means change and dynamism.

But if you refuse to embrace your past at all, you are rejecting any meaning in your being alive.  If you act like the past has never been, then you have no way of making sense of what you do now.  Because what you do now will soon be the past and by your own principles should be ignored as if it had never been.

You must have growth within continuity.  We call that repentance.

Repentance cannot be just a rejection of your past behavior.  It must be an improvement on it.  Like as The Great Divorce, you must discover what you were really looking for.  Like in Berger’s City of Earthly Desire, you must work through your past, understand it, make some meaning of it.

Then God remembers your sin no more, because it is no longer sin.  What He does recall with perfect clarity is your story of growth and grace and overcoming, of which what once was your sin is a part.