The Council of Trent — which firmly reasserted Catholic doctrine in the face of the Protestant Reformation — concluded its last session exactly 450 years ago on Dec. 4, inspiring a renaissance of Catholic art and spirituality that shaped the life of the Church for nearly half a millennium.

"Trent created the form of Catholicism that evangelized the New World, that gave birth to many saints and that successfully met the challenge of the political madnesses of the 19th and 20th centuries. That’s a noble legacy," said Catholic author George Weigel.

The Council of Trent was convened on Dec. 13, 1545, in Trento, Italy — 28 years after an Augustinian monk named Martin Luther nailed his Ninety-Five Theses to a church door, igniting the Protestant Reformation. The bishops, abbots and theologians at Trent responded to the issues raised by Luther and other Protestants in 25 sessions over nearly two decades, adjourning on Dec. 4, 1563.

Trent addressed some of the most fundamental questions of Christianity, such as the relationship between Scripture and Tradition and the nature and number of the sacraments.

"One was the question of: How are we saved? Are we saved by grace alone or are we saved by works alone — good works alone? Or are we saved by some combination of grace and good works? Of course, the Lutherans said by grace alone," said Jesuit Father John O’Malley, a Georgetown University historian and author of Trent: What Happened at the Council. "The Council of Trent wrestled with this problem and said we’re primarily saved by grace. We do not save ourselves, yet, in some limited way, some small way, with the help of grace, we do contribute to our salvation. We’re not puppets of grace. We have to cooperate in some way."

In addition to the debate over salvation, Trent confirmed the sevenfold number of the sacraments, set the canon of Old and New Testaments, declared that Scripture and Tradition are both authoritative, affirmed the sacrificial nature of the Mass and unhesitatingly renewed its commitment to the doctrine of transubstantiation, which holds that the substance of bread and wine in the Eucharist is wholly changed over into the substance of Christ’s body and blood.

Sweeping Reforms

But Trent also launched a sweeping reform of Church life that affected everything from how people become married to how they learn about the faith, laying the foundation for institutions and practices that Catholics today take for granted, historians say.

"They wanted to bolster the spiritual and moral character of the clergy, which had been one of the contributing factors to the Reformation. They wanted to kindle a similar kind of piety in laypeople. And they wanted to make the Church more missionary or evangelical," said James Hitchcock, a historian at St. Louis University and author of History of the Catholic Church: From the Apostolic Age to the Third Millennium.

Another fundamental reform was the institution of the seminary, where candidates for the priesthood would be trained in theology, receive spiritual formation and be evaluated by their superiors for their suitability for the priesthood. "All of that sort of seems like common sense, but, as a matter of fact, there were no seminaries prior to the 16th century," Hitchcock said.

The Catechism — a Church-approved compendium of core teachings in terms accessible to the laity — also was borne out of Trent, according to Hitchcock. "Again, what an obvious thing to have, but they didn’t have one prior to the Council," he said.

Trent left its mark on marriage too, mandating that priests be witnesses for marriages. The rule was targeted at secret marriages, in which couples would privately exchange vows, enabling one spouse to abandon the other, denying there ever was a marriage, according to Father O’Malley.

Lessons for Today

Trent’s anniversary is a time not only to celebrate its legacy, but also to reflect on lessons for the present.

"Trent shows us how the Church can meet the challenge of new cultural and political circumstances with intelligence and pastoral courage — and strong Church leadership," Weigel said.

Trent is an object lesson in the universality of the Church’s teachings and practices, according to Father Joseph Lee, academic dean at Our Lady of Guadalupe Seminary near Lincoln, Neb., which is run by the Priestly Fraternity of St. Peter (FSSP).

"This can be a healthy corrective to an over-emphasis on ‘inculturation,’ which has proved over the last few decades to have been as much a source of problems and confusions as of enrichment in the Church’s life," he said. Catholics also would do well to emulate Trent’s focus on carefully defined principles as a "basis for theological work and formation," Father Lee said.

Even as we celebrate Trent’s legacy, we should not go too far in applying it to the present, Weigel warned. "The mistake comes when we think we can freeze-frame Tridentine Catholicism, as if it were a mode of being Catholic applicable to every cultural and historical circumstance," he said.

 The legacy of Trent is perhaps clearer today than it was just half a century ago.

"When Vatican II was going on and right after it ended, a lot of people were specifically saying that [it] was a repudiation of the Council of Trent," Hitchcock said. According to proponents of this view of the Second Vatican Council, there would now be less emphasis among Catholics on doctrinal orthodoxy and on studying the Catechism, and seminary formation would be fundamentally revised because, previously, it was too rigid and had produced unworldly and somewhat irrelevant priests.

"Much effort was put into repudiating Trent as a way of implementing Vatican II," Hitchcock said. "It took a generation of work by important theologians, of whom Pope Benedict was one, to emphasize the spirit of continuity which needs to exist rather than one of rupture."

That "hermeneutic of continuity" was recently reaffirmed by Pope Francis in a Nov. 19 letter to Cardinal Walter Brandmuller for the 450th anniversary of Trent.

"Graciously hearing the very same Holy Ghost, the holy Church of our age, even now, continues to restore and meditate upon the most abundant doctrine of Trent. As a matter of fact, the ‘hermeneutic of renewal’ … which our predecessor Benedict XVI explained in 2005 before the Roman Curia, refers not only to the Tridentine Council, but also to the Vatican Council," Pope Francis wrote.

Of course, continuity implies both harmony with and change from the past. Indeed, were the Fathers of Trent to come back today, they would be "puzzled by a lot of things they saw," Hitchcock said.

"And it would take some time to speak, to investigate and explain and so forth … to let them see the spirit of continuity which is there," Hitchcock said. "We are always doing both: We’re maintaining continuity, and at the same time, we’re innovating in various ways."

Stephen Beale writes from

Providence, Rhode Island.