Philo on the Philosopher - King
Claus Sluter's Moses (figure in Sluter's Well of Moses, Charterhouse of Champmol near Dijon, 1395-1406
"There are four adjuncts to the truly perfect ruler. He must have kingship, the faculty of legislation, priesthood and prophecy, so that in his capacity of legislator he may command what should be done, as priest dispose not only things human but things divine, as prophet declare by inspiration what cannot be apprehended by reason. I have discussed the first three, and shown that Moses was the best of kings, of lawgivers and of high priests, and will go on to show in conclusion that he was a prophet of the highest quality."
Philo. On the Life of Moses. Translated by F.H. Colson. Cambridge, MA, 1957.