Summi Pontificatus §53

⁵³ Once the authority of God and the sway of His law are denied in this way, the civil authority as an inevitable result tends to attribute to itself that absolute autonomy which belongs exclusively to the Supreme Maker. It puts itself in the place of the Almighty and elevates the State or group into the last end of life, the supreme criterion of the moral and juridical order, and therefore forbids every appeal to the principles of natural reason and of the Christian conscience. We do not, of course, fail to recognize that, fortunately, false principles do not always exercise their full influence, especially when age-old Christian traditions, on which the peoples have been nurtured, remain still deeply, even if unconsciously, rooted in their hearts.