Man must, therefore, take his standard of a loyal and religious life from the eternal law; and from all and every one of those laws which God, in His infinite wisdom and power, has been pleased to enact, and to make known to us by such clear and unmistakable signs as to leave no room for doubt. And the more so because laws of this kind have the same origin, the same author, as the eternal law, are absolutely in accordance with right reason, and perfect the natural law. These laws it is that embody the government of God, who graciously guides and directs the intellect and the will of man lest these fall into error. Let, then, that continue to remain in a holy and inviolable union which neither can nor should be separated; and in all things -- for this is the dictate of right reason itself -- let God be dutifully and obediently served.
--Pope Leo XIII,
Libertas Praestantissimum, 1888
