A Claim Worth Testing

The argument, when it is made, runs roughly like this: the Divine Liturgy served in Orthodox parishes today is substantially the same rite the apostles themselves would recognize, preserved by a Church that jealously guards against innovation—while the Roman Rite was reshaped, truncated, and finally re-invented by a papacy willing to legislate its liturgical life into whatever shape suited the moment. It is a serious claim, and it deserves a serious answer rather than a defensive one. This article is not a defense of any twentieth-century liturgical reform; it stays with the historical record from the patristic era through the sixteenth century, where the claim is actually made and can actually be tested. And tested against that record, both halves of the claim turn out to be wrong in the same way: both liturgical traditions show real, substantial, documented development—some of it slow and organic, some of it fast and disruptive—and neither tradition’s own best historians pretend otherwise.

The Roman Rite’s Own Layered History

The Roman Canon itself, the oldest core of the Latin Mass, did not arrive whole. St. Ambrose’s fourth-century catechetical work De Sacramentis preserves an institution-narrative prayer close to, but not identical with, the Canon used today—its chalice formula reads “Hic est sanguis meus,” matching the Syrian liturgical tradition rather than the Roman Canon’s current wording. Fortescue, reporting a comparative-liturgy hypothesis associated with Baumstark, describes a further structural reordering proposed for the fifth century, shifting the Canon’s internal sequence to align more closely with Alexandrian rather than Antiochene anaphoral patterns—crediting the initiating changes to Pope Leo I and the final recasting to Gregory the Great. This remains a historical hypothesis about a very early period, not an uncontested modern consensus, but it is telling that even a century-old, traditionally-minded scholarly account already assumed real structural change, not stasis. Even the tradition’s own account of Gregory’s role, recorded by John the Deacon nearly three centuries after the fact, describes him “leaving out much, changing little, adding something”—light redaction of an existing text, not fresh composition.

The Missal itself passed through the same kind of layering. The Old Gelasian Sacramentary, a manuscript of around 750, is a Frankish-Roman hybrid—its underlying Roman material datable by internal evidence to roughly the seventh century, its traditional attribution to Pope Gelasius I resting on what modern scholarship considers far too thin a basis to sustain. The Gregorian Sacramentary sent to Charlemagne in the 780s was itself supplemented a generation later by Frankish material—traditionally credited to Alcuin, now attributed to Benedict of Aniane—in a composite book whose own scribe marked the seam explicitly: “Hucusque” (“up to here”) is the preceding book of Gregory; what follows is drawn “partly from the Gelasian book, partly from Gallican sources.” That Frankish-edited composite then returned to Rome in the ninth through eleventh centuries and supplanted the older purely Roman books there. The Roman Rite, in other words, was reshaped by its own export to Francia and re-import back to Rome centuries before Trent.

Against that background, the Missal of Pius V, promulgated by the 1570 bull Quo Primum, was explicitly framed by its own authors as restoration, not invention—the bull’s own language says its compilers “restored the Missal itself to the pristine form and rite of the holy Fathers” after collating ancient manuscripts. Adrian Fortescue’s classic study is direct: the 1570 commission’s mandate “was not to make a new missal, but to restore the existing one ‘according to the custom and rite of the holy Fathers,’ using for that purpose the best manuscripts and other documents.” Fr. Uwe Michael Lang’s more recent scholarship, published in the Adoremus Bulletin and expanded into a full Cambridge University Press monograph, confirms the same conclusion with modern apparatus: the 1570 Missal “stands in continuity with the plenary missals of the Roman Rite in the form used by the papal curia, which go back to the 13th century,” itself extending back further to the Gregorian reform and Ordo Romanus I. Trent’s own real editorial work was concrete and specific—suppressing the troping of the Introit, Kyrie, and Gloria; reducing dozens of medieval sequences to four; trimming an overgrown sanctoral calendar—restoration and pruning, exactly as Fortescue says, not composing from nothing.

The Byzantine Rite’s Own Layered History

The claim of unbroken Byzantine continuity does not fare better under the same kind of scrutiny—and the person best positioned to say so is not a Western critic but Fr. Robert Taft, the leading modern scholar of Byzantine liturgical history and himself a Jesuit priest of the Byzantine Rite. Taft’s own account of the Divine Liturgy’s formation identifies at least three substantially distinct synthesis periods, not one continuous line: the older cathedral rite of Hagia Sophia and the Great Church of Constantinople, known as the Asmatike Akolouthia or “Sung Office”; a monastic “Studite” synthesis (roughly 800–1204), inaugurated by St. Theodore of Stoudios and drawing heavily on practices imported from the monks of St. Sabas in Palestine, which supplanted the older cathedral rite after the Byzantine restoration of 1261; and a further “neo-Sabaitic” synthesis that gradually modified and ultimately supplanted the Studite rite itself during the fourteenth-century hesychast ascendancy.

Nikon: The Sharpest, Most Concrete Parallel

If the objection is not merely “liturgies develop slowly over centuries” but specifically “a single authority centrally imposed rapid, disruptive liturgical change”—the sharper version of the Roman charge—Orthodoxy has its own unambiguous instance, and a more recent one than anything in the Roman story. Patriarch Nikon of Moscow, beginning in 1653, revised the Russian service books to conform to contemporary Greek printed editions: the sign of the cross shifted from two fingers to three, the direction of processions reversed, the number of prosphora changed, and the spelling of the Holy Name itself was altered. Those who resisted—the Old Believers—were formally anathematized at the Synod of 1666–1667, and many suffered exile, imprisonment, or death for refusing the new books. The schism has never healed; Old Believer communities survive as a distinct body to this day.

Where the Comparison Needs a Fair Limit

Honesty requires conceding what a fair Orthodox reader would rightly press here. The term this whole argument leans on—“organic development”—is not as settled or as neutral as either side’s popular apologetics assumes. Robert Taft’s own foreword to a modern edition of Anton Baumstark’s foundational work on liturgical development notes that “a river of ink has been spilt” over Baumstark’s proposed “laws of liturgical evolution.” Fritz West’s introduction to the same volume goes further, distinguishing a careful, descriptive use of “organic” from a prescriptive, almost ideological one—naming Alcuin Reid and László Dobszay as examples of a use that treats “organic” as a standard by which to judge a reform’s legitimacy after the fact. Even sympathetic commentators dispute where the line falls: one traditionalist Catholic liturgical writer has argued that no liturgical change is ever truly “organic” in a strict sense, since “decision is not an organic process”—every reform, gradual or sudden, ultimately involves someone deciding.

That concession cuts in a specific direction, not a vague one: there remains a real, meaningful difference between slow, cumulative development within a received tradition—which is what both the Gelasian-to-Gregorian layering and the Studite-to-neo-Sabaitic transition actually were, each unfolding across generations without a single decree imposing it all at once—and a rapid, centrally decreed reform imposed on an entire Church within a few years, which is what Nikon’s reform actually was. Trent’s 1570 codification sits closer to the first category than the second: a commission’s editorial pruning of an already-existing, centuries-deep textual tradition, explicitly carved with exemptions for other equally ancient local uses. Conceding that distinction plainly is not a retreat from this article’s argument. It is what earns the right to make it.

The Verdict