VATICAN CITY — With the threat of schism and excommunication hanging over them, a breakaway group of traditionalist Catholics is set to directly defy Pope Leo XIV by consecrating four bishops without his consent.

The Society of St. Pius X has planned a massive ceremony Wednesday at its seminary in Econe, Switzerland, in a mountain valley in the country’s southwest corner. It’s expected to draw thousands of people who prefer the ancient Latin Mass over the modern liturgies celebrated in most of the Catholic Church.

The society, known by its acronym SSPX, is going ahead with the consecrations despite a last-ditch appeal by Leo to call it off. In a letter published Tuesday, the American pope warned that consecrating bishops without his approval amounts to a “sin of extreme gravity” that will actually harm their faithful.

According to church law, the mere act of consecrating a bishop without a papal mandate incurs the harshest penalty in the Catholic Church: automatic excommunication for the four new bishops and the bishop administering the rite. It also amounts to a schismatic act, or an intentional rupture of the unity of the Catholic Church.

And yet everything about Wednesday’s ceremony has the air of a joyous celebration. The SSPX website for its consecration has had a countdown clock running for days. Video clips show seminarians joyfully unloading boxes. Participants will receive a baseball cap with the “Econe2026” seal on it.

And in perhaps the most obvious sign of a celebration, registered participants can purchase a souvenir set of wine to commemorate the “historic” event. The 75 Swiss franc ($92.50) “Cuvee des Sacres” gift box features pinot noir, Syrah, Petit Arvine and Fendant, each bottle with a bishop-themed label: an image of a bishop’s pointed miter hat, his ring, cross or crozier staff.

For the SSPX, neither the threat of a declared schism nor an excommunication matters. The SSPX believes it alone is upholding church tradition and the Catholic faith.

“We don’t fear it. It pains us immensely, but we believe that the good we seek is greater than the pain that will be inflicted upon us,” said Marc-André Mabillard, media manager for the society.

In a late response to Leo’s letter, the SSPX superior, the Rev. Davide Pagliarani, urged Leo to wait before declaring any penalty.

The ceremony is taking place 38 years to the day after the Vatican declared the last consecrations of SSPX bishops a “schismatic act” that incurred automatic excommunication for the bishops.

The French Archbishop Marcel Lefebvre had founded the ultratraditionalist SSPX in opposition to the modernizing reforms of the Second Vatican Council. Among other things, the 1960s church meetings revolutionized the Catholic Church’s relations with other Christians, Jews and people of other faiths, and allowed Mass to be celebrated in the vernacular rather than Latin.

Today, the SSPX celebrates the ancient Latin Mass and has accused the modern church of being rife with heresies and errors, including modernism, liberalism and ecumenism. The society insists that only the SSPX is upholding the true faith of Christ and has justified the consecrations, citing a “state of necessity” to minister to its faithful.

But many Catholics, including conservative and traditional ones, are opposed to the consecrations, viewing them as an act of severe disobedience to the pope that hurts the church.

“You can’t serve tradition while disobeying the church and her authority,” said the Rev. Robert Gahl, an ethics expert at the Catholic University of America.

The St. John Paul II biographer George Weigel has written that the SSPX-Vatican divide is about far more than just whether Mass is celebrated in Latin or English.

It’s about “a rejection of the Second Vatican Council’s teaching on the church, salvation, religious freedom, church–state relations, and the church’s relationship to other religions,” Weigel wrote recently in First Things magazine.

Weigel recalled that Lefebvre was a supporter of the “collaborationist” Vichy regime in France during World War II. One of its original SSPX bishops denied the Holocaust.

The SSPX has justified the consecrations by invoking a “state of necessity.” The group says that with only two of the original four bishops surviving, it simply needs more bishops to tend to the needs of a faith community that counts 800 places of worship in 77 countries.

The group denies that the consecration is a rejection of Leo’s authority or a challenge to his power. Rather, it says the creation of four new bishops is solely to be able to ordain new priests and preside over confirmation ceremonies according to the ancient rite.

The SSPX has identified the new bishops as Pascal Schreiber of Switzerland, Michael Goldade of the United States, Michel Poinsinet de Sivry of France and Marc Hanappier, also of France.

In response to the pope’s letter, Mabillard, media manager for the society, expressed “great sadness to not be understood by our leader,” and added: “We are changing absolutely nothing in our plans.”

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Keaten contributed from Geneva.

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