We Must Obey God Rather Than Men

All who rule, therefore, would hold in honour the holy name of God, and one of their chief duties must be to favour religion, to protect it, to shield it under the credit and sanction of the laws, and neither to organize nor enact any measure that may compromise its safety. This is the bounden duty of rulers to the people over whom they rule.

And just as the end at which the Church aims is by far the noblest of ends, so is its authority the most exalted of all authority, nor can it be looked upon as inferior to the civil power, or in any manner dependent upon it.

In regard to things temporal, religion is the source of benefits as manifold and great as if the chief end of her existence were to ensure the prospering of our earthly life. And, indeed, wherever the Church has set her foot she has straightway changed the face of things, and has attempered the moral tone of the people with a new civilization and with virtues before unknown. All nations which have yielded to her sway have become eminent by their gentleness, their sense of justice, and the glory of their high deeds.

And yet a hackneyed reproach of old date is levelled against her, that the Church is opposed to the rightful aims of the civil government, and is wholly unable to afford help in spreading that welfare and progress which justly and naturally are sought after by every well-regulated State. From the very beginning Christians were harassed by slanderous accusations of this nature, and on that account were held up to hatred and execration, for being (so they were called) enemies of the Empire. The Christian religion was moreover commonly charged with being the cause of the calamities that so frequently befell the State.

When it is said that the Church is hostile to modern political regimes and that she repudiates the discoveries of modern research, the charge is a ridiculous and groundless calumny.
http://www.vatican.va/holy_father/leo_xiii/encyclicals/documents/hf_l-xiii_enc_01111885_immortale-dei_en.html

These and like errors, it is clear, have crept in among certain of Our sons who are deceived by imprudent zeal for souls or by false science. To them We are compelled with grief to repeat once again truths already well known, and to point out with solicitude clear errors and dangers of error.
http://www.vatican.va/holy_father/pius_xii/encyclicals/documents/hf_p-xii_enc_12081950_humani-generis_en.html