The law is not known, since there is nothing in it to know. We come across it only through its action, and it acts only through its sentence and its execution. It is not distinguishable from the application. We know it only through its imprint on our heart and our flesh: we are guilty, necessarily guilty. Guilt is like the moral thread which duplicates the thread of time.
Kant's Critical Philosophy: The Doctrine of the Faculties (ed. Bloomsbury Publishing, 2008) - ISBN: 9781441120939