Gregory the Dialogist : Hence under the divine law the priest receives the shoulder for sacrifice, and this the right one and separate; to signify that his action should be not only profitable, but even singular; and that he should not merely do what is right among bad men, but transcend even the well-doers among those that are under him in the virtue of his conduct, as he surpasses them in the dignity of his order. — The Book of Pastoral Rule, Part 2, Chapter 3