Replies

He (Pope St. PiusV) solemnly established this rite of Mass as a regula fidei by his Apostolic Bull Quo Primum of July 14, 1570. This Bull was republished in subsequent editions of the missal by his papal successors, as a sign of continuity in the lex orandi, precisely so that the lex credendi might be fully preserved and handed down.

In stark contrast, the liturgical books promulgated by Paul VI were fashioned out of bits and pieces of older Western books and non-Western sources, spliced in with new compositions, and unmoored from a linguistic, rubrical, and musical heritage that was shared, with local variations, by all Christians prior to the Reformation. His (Paul VI's) missal was the first since 1570 not to be prefaced with Quo Primum, an eloquent absence that testifies to its discontinuity from the preceding tradition. Call it what you will, this interruption of transmission is what made possible in the first place the confusing situation to which Summorum Pontificum was directed as a pastoral response.