Jake has the T. S. Eliot poem I was going to use, so here, instead, is this bit of The Brothers Karamazov by Fyodor Dostoevsky. (Hat tip, Deacon Vicki Black:)
“No one can commit so great a sin as to exhaust the infinite love God. Or can there be a sin that would exceed the love of God? Only you must never forget to think continually of repentance, but dismiss your fear altogether. Believe that God loves you in a way you cannot even conceive of. He loves you in spite of your sin and in your sin. So go and do not be afraid.”