Luther: Sin is in us like a beard

I'm reading through Joel Beeke's new book Living for God's Glory (Reformation Trust, 2008).

In his discussion of the doctrine of sin, Beeke quotes Martin Luther (who is frequently depicted with more than his fair share of stubble):

Original sin is in us like a beard. We are shaved today and look clean; tomorrow our beard has grown again, nor does it cease growing while we remain on earth. In like manner original sin cannot be extirpated from us; it springs up in us as long as we live" (p. 54).

What a great metaphor for Luther's contention that the Christian is simul iustus et peccator (at the same time just and a sinner).

JTR