Pius IX, 1846-1878

but faith frees reason from all errors and, by a knowledge of divine things, wonderfully elucidates it, confirms, and perfects it [cf. n. 1799].

1636. And with no less deceit certainly, Venerable Brothers, those enemies of divine revelation, exalting human progress with the highest praise, with a rash and sacrilegious daring would wish to introduce it into the Catholic religion, just as if religion itself were not the work of God but of men, or were some philosophical discovery which can be perfected by human means [cf. n. 1705]. Against such unhappily raving men applies very conveniently, indeed, what Tertullian deservedly made a matter of reproach to the philosophers of his own time: "Who have produced a stoic and platonic and dialectic Christianity."¹ And since, indeed, our most holy religion has not been invented by human reason but has been mercifully disclosed to men by God, thus everyone easily understands that religion itself acquires all its force from the authority of the same God speaking, and cannot ever be drawn from or be perfected by human reason.

1637. Indeed, human reason, lest it be deceived and err in a matter of so great importance, ought to search diligently for the fact of divine revelation so that it can know with certainty that God has spoken, and so render to Him, as the Apostle so wisely teaches, "a rational service" [Rom. 12:1]. For who does not know, or cannot know that all faith is to be given to God who speaks, and that nothing is more suitable to reason itself than to acquiesce and firmly adhere to those truths which it has been established were revealed by God, who can neither deceive nor be deceived?

1638. But, how many, how wonderful, how splendid are the proofs at hand by which human reason ought to be entirely and most clearly convinced that the religion of Christ is divine, and that "every principle of our dogmas has received its root from above, from the Lord of the heavens,"² and that, therefore, nothing is more certain than our faith, nothing more secure, that there is nothing more holy and nothing which is supported on firmer principles. For, in truth, this faith is the teacher of life, the index of salvation, the expeller of all faults, and the fecund parent and nurse of virtues, confirmed by the birth, life, death, resurrection, wisdom, miracles, prophecies of its author and consummator, Christ Jesus; everywhere resplendent with the light of a supernatural teaching and enriched with the treasures of heavenly riches, especially clear and significant by the predictions of so many prophets, by the splendor of so many miracles, by the constancy of so many martyrs, by the glory of so many saints, revealing the salutary laws of Christ and acquiring greater strength every day from these most cruel persecutions, (this faith) has pervaded