The Commonitorium

[84.] The foregoing would be enough and very much more than enough, to crush and annihilate every profane novelty. But yet that nothing might be wanting to such completeness of proof, we added, at the close, the twofold authority of the Apostolic See, first, that of holy Pope Sixtus, the venerable prelate who now adorns the Roman Church; and secondly that of his predecessor, Pope Celestine of blessed memory, which same we think it necessary to insert here also.

Holy Pope Sixtus then says in an Epistle which he wrote on Nestorius’s matter to the bishop of Antioch, “Therefore, because, as the Apostle says, the faith is one,—evidently the faith which has obtained hitherto,—let us believe the things that are to be said, and say the things that are to be held.” What are the things that are to be believed and to be said? He goes on: “Let no license be allowed to novelty, because it is not fit that any addition should be made to antiquity. Let not the clear faith and belief of our forefathers be fouled by any muddy admixture.” A truly apostolic sentiment! He enhances the belief of the Fathers by the epithet of clearness; profane novelties he calls muddy.

[85.] Holy Pope Celestine also expresses himself in like manner and to the same effect. For in the Epistle which he wrote to the priests of Gaul, charging them with connivance with error, in that by their silence they failed in their duty to the ancient faith, and allowed profane novelties to spring up, he says: “We are deservedly to blame if we encourage error by silence. Therefore rebuke these people. Restrain their liberty of preaching.” But here some one may doubt who they are whose liberty to preach as they list he forbids,—the preachers of antiquity or the devisers of novelty. Let himself tell us; let himself resolve the reader’s doubt. For he goes on: “If the case be so (that is, if the case be so as certain persons complain to me touching your cities and provinces, that by your hurtful dissimulation you cause them to consent to certain novelties), if the case be so, let novelty cease to assail antiquity.” This, then, was the sentence of blessed Celestine, not that antiquity should cease to subvert novelty, but that novelty should cease to assail antiquity.