We sternly urge adherence to the established norms by those who raise an uproar or a challenge in the name of a misunderstood creative freedom, and thus inflict so much harm on the Church with their rash innovations, so vulgar, so frivolous—and sometimes even lamentably profane. Otherwise the essence of dogma and obviously of ecclesiastical discipline will be weakened, in line with the famous axiom: "lex orandi, lex credendi." We therefore call for absolute loyalty so that the rule of faith may remain safe.
— Pope Paul VI (27 June 1977)