ON THE SACRED LITURGY
SOLEMNLY PROMULGATED BY
POPE PAUL VI
ON DECEMBER 4, 1963
26. Liturgical services are not private functions, but are celebrations of the Church, which is the "sacrament of unity," namely, the holy people united and ordered under their bishops 
Therefore liturgical services pertain to the whole body of the Church; they manifest it and have effects upon it; but they concern the individual members of the Church in different ways, according to their differing rank, office, and actual participation.
The heart of Paragraph 26 is the opening sentence, a quotation from St. Cyprian of Carthage, a bishop from North Africa (c. 200-258 A.D.). Cyprian’s writings on the Church are the fruit of a very difficult age: the Roman persecutions of the churches in North Africa. The writings of Cyprian which have survived are not voluminous, and Cyprian was not a systematic “theologian” in the sense of St. Augustine, two centuries later. He was an influential Church leader on his continent, more preacher/administrator than philosopher, but his texts are the foundations of an important institutional component of worship and sacraments, that they be signs of unity.
Cyprian’s concern for unity in sacraments was the result of probably the first great crisis in sacramental discipline, the issue of reunion with the Church after serious sin, or what we would call today sacramental or canonical Penance. As a sitting bishop, Cyprian experience two waves of Roman persecution; during the second wave, he himself was beheaded. But he survived the first persecution and was thus confronted with the fallout that faced other bishops like himself. The Roman persecutors had put many Christians to the test: the faithful were subjected to a variety of intimidations, ranging from confiscation of goods to torture to actual sentence of death.
A Christian could avoid or reduce his torments if he or she repudiated membership in the Church and voluntarily made a gesture of worship toward a Roman deity. (On the standard marriage application form found in any parish office today, there is or should be a canonical question, “Have you ever left the Catholic Church by a formal act?” I guess publicly worshipping a Roman deity would serve as an affirmative answer.) In ancient times, the term for abandoning the faith in persecution was apostacy, a grave sin in the eyes of the Church given the horrific sufferings of those who remained faithful to Christ. Witnesses of the times chronicled the most heroic sufferers, and the most famous of these sufferers are celebrated in our Church calendar: Sebastian, Lawrence, Agnes, Cecelia, etc.—and some are remembered in today’s Eucharistic Prayer I.
After the first persecution, Cyprian actually faced a twin problem. He was confronted with a small group of living survivors of Roman violence—those maimed and scarred in ghastly ways who enjoyed a kind of charismatic authority among the faithful that exceeded the ordinary authority of a consecrated bishop. In fact, the intercession of a “living martyr” seems to have been a component of the earliest rites of Penance. Cyprian would have been sensitive to the extraordinary role of these heroes and heroines vis-à-vis the normative rule of bishops who shared in the authority of the apostolic succession through the laying on of hands.
But by far his greater challenge came from the other extreme, those guilty of the sin of apostasy. What was to become of them? It is hard to know percentages as no data exists, but given the prolonged controversy that ensued, it is fair to say that a good number of Christians apostatized. In fact, Cyprian himself came under some scrutiny here, as Roman officials targeted bishops for execution. Cyprian undertook a self-imposed exile during the first persecution, on the not unreasonable argument that the local churches needed living shepherds as much as hallowed martyrs.
When Cyprian returned to Carthage, he discovered that pastoral practice in his absence had taken two distinct directions. In some cases, the apostates (known as lapsi) were received back into full communion with little or no fanfare. Other Church leaders held that the lapsi could never reenter the Christian assembly. Cyprian took a middle position: that lapsi might seek full reception to the Eucharist through the one-year process of canonical or sacramental penance. Cyprian summoned all the North African bishops to a synod in Carthage, where his moderate position became standard except among extremists who agitated into the fourth century virtually to the time of Constantine. It is important to add that Rome itself suffered the same divisions during persecutions there.
Cyprian’s experience and writings are brought into Vatican II for multiple reasons. His quote in para. 26 stresses the importance of unity in the Church as it gathers for Eucharist with its bishop (or today, with his authorized surrogate, the ordained priest.) In Cyprian’s thinking the primacy of the Apostolic Tradition was nowhere more visible than in the breaking of bread by a legitimate successor of the apostles, i.e., a bishop, in union with the faithful. The power of liturgy, then, is derived from the Spirit-filled successors of the apostles.
Para. 26, citing Cyprian, also makes a compelling argument about Church governance. The third-century bishop was a strong proponent of an institutionally structured Church, built around the office of the bishop. (Theology books use the term “monarchical bishops.”) As much as Cyprian respected the “living martyrs” of his day, he did not cede to them an authority parallel to that of duly consecrated bishops in the Apostolic Tradition. The Church today does not deny that the Holy Spirit grants unique gifts, virtues, and insight upon any baptized persons—gifts referred to biblically as “charisms” as in charismatic—but as an institution the Church leads through what it has received from Scripture and the collective wisdom of bishops and their faithful.
As a historical sidebar, I should add that during Vatican II, one of the biggest complaints of many of the bishops in attendance was the diminished regard for the office of the episcopacy and a nineteenth century shift toward a monarchical papacy. In practice, they complained, the Church put all authority in the hands of the pope, who doled out whatever governing powers local bishops needed. The bishops rightfully argued that by the Sacrament of Order they enjoyed Apostolic authority themselves that needed expression in the governance of the Church. Consequently, the Council and the Vatican agreed to regular consultations or synods of bishops, the most recent being Pope Francis’ Synod on Marriage and the Family two years ago.
Para. 26 also addresses a common practice in 1963, the “private Mass.” A priest was expected to offer Mass daily; most priests regarded their daily Mass as a privilege of their ordination. In parishes, the priest’s daily Mass would have been a public parish Mass. On vacations, it was common practice for a priest to seek permission to offer Mass—publicly or privately—in the closest church. But in religious communities such as my seminary, there might be as many as twenty priests living under the same roof with only one “public” Mass, that being for the seminarians. Thus, our seminary church—like many of the old churches and cathedrals you might see today in your travels—was lined with smaller side altars; I believe we had twelve altars along with the main altar at the front. It was not unusual at around 6:30 AM for all thirteen altars to be in use at the same time—the seminarians Mass from the high altar, and twelve individual Masses offered by twelve individual priests at the same time, with one altar server in attendance at each one.
Even before Vatican II there was discussion among academics about the idea of “concelebration,” where all priests in a church or institution might celebrate Mass together. Para. 26 proposes that the idea of Mass as a “private function” be replaced with the better understanding of Mass as a sacrament of unity, both within the priesthood and with the faithful at large. I was a sacristan in 1967 when my seminary began to offer concelebrated Masses as standard fare, with many of my teachers celebrating Mass together. Some older clergy found the concelebrations difficult to accept and continued to offer the private side altar Masses. I do not know if any newly ordained priests have brought back the private Mass for their own reasons, but Church law and practice strongly favors fewer and better attended Masses as appropriate sacramental signs of the unity of the Church.