Leo will visit one of world’s most “glass-heavy” cathedrals

On September 28, 2026, Pope Leo XIV will celebrate Mass at St. Stephen’s Cathedral in Metz. This represents a rare privilege for the diocese; it’s the only French cathedral in the Holy Father’s itinerary to host a papal Mass during his upcoming trip.

While the Pope is also scheduled to visit Notre Dame de Paris, he will only preside over Vespers there. The large-scale Mass planned for Lourdes will be held outdoors on the shrine’s grounds rather than inside the basilica.

Standing with a nave reaching 135 feet, Metz Cathedral is the third-highest in France; only the cathedrals of Beauvais and Amiens are taller. Its architectural grandeur and historical significance make it a fitting stage for this singular event in the Pope’s French itinerary.

Commonly nicknamed “God’s lantern,” the cathedral is one of the most glass-heavy Christian structures in the world. It boasts nearly 70,000 square feet of stained glass — a staggering amount compared to the 28,000 square feet found at Chartres Cathedral.

The collection of stained glass dates from the 13th to the 20th century. It features works by the most renowned master glassmakers of every era. On the western facade, visitors can admire the 14th-century great rose window by Hermann de Münster, which measures nearly 40 feet in diameter. Near the transept, the timeline jumps forward to the Renaissance. There, the masterwork of Valentin Bousch, a celebrated glassmaker from the Lorraine region, glows vibrant yellow, red, blue, and green.

But Metz also possesses an incredible collection of contemporary stained glass; the cathedral has always sought out the finest artists of the day. Following the devastation of World War II, the Church commissioned painters including Jacques Villon and Marc Chagall to replace windows lost in the conflict.

The windows by Villon are the only stained-glass works he produced in his lifetime. Located in the Chapel of the Blessed Sacrament, these pieces depart from the cathedral’s traditional figurative style. Instead, they use abstract geometric shapes to evoke scenes from the Exodus, the Last Supper, the Crucifixion, and the Wedding at Cana.

Among the most prestigious artists to contribute to the cathedral is Marc Chagall. He began work on the windows for the north apse in 1959. Chagall had previously experimented with the medium at Chartres and Assy. Although he turned to glass late in his career, he felt a spiritual necessity to master it.

“Stained glass transmutes physical light into spiritual light,” the artist once declared. For Chagall, the medium was a response to a deep personal malaise. “The world in which I live is closed,” he said.

In the art of glass, he found a path to openness. With glass, the world opens itself to the light. Obsessed with this idea, he created a magnificent window centered on the theme of Creation. A flamboyant, fiery yellow is dominant — a color perfectly suited to brighten the “lantern of God” for the arrival of Pope Leo XIV.