Editor’s note: On this feast day of St. Januarius, a look back on something that has not happened in the presence of a pope since Pius IX.

The blood relic of St. Gennaro, patron saint of Naples, today miraculously liquefied in the presence of Pope Francis, the first time the miracle has occured in the presence of a pontiff since 1848.

“His blood has half-liquefied,” the Archbishop of Naples, Cardinal Crescenzio Sepe, said at the conclusion of Pope Francis’ address to diocesan priests and religious in the city’s cathedral. “It’s a sign that St. Gennaro loves the Pope, who is Neapolitan like us.”

Pope Francis immediately and lightheartedly replied: “The archbishop said the blood is half-liquefied. It means the saint loves us halfway. We all have to convert a little more so that he loves us more.”

Today’s wondrous occurance knows just one precedent. It is the first time St. Gennaro’s blood relic has liquefied in the presence of a pontiff since the miracle occurred in the presence of Pope Pius IX in 1848.

Pius IX was the longest-reigning elected pope in the history of the Catholic Church (31 years). He convened the First Vatican Council, which decreed papal infallibility; defined the dogma of the Immaculate Conception of the Blessed Virgin Mary, meaning that Mary was conceived without original sin; and he was the last Pope to rule as the sovereign of the papal states which fell to the Italian army in 1870.

Fleeing the Mazzini riots in 1848, Pope Pius IX was rescued by a ship sent by Francis II of Bourbon, who took him to the Royal Palace of Portici. The Pope expressed his desire to go to the Cathedral of Naples. There the miracle of St. Gennaro occurred in his presence.

As a token of his gratitude, the pontiff donated a golden chalice to the cathedral in the saint’s honor. The chalice is today numbered among the “Ten Wonders of the Treasure of St. Gennaro.”

As Cardinal Sepe today announced the miracle, in the adjacent streets people could be heard shouting with neapolitan passion: “It’s a miracle, it’s a miracle!”

In fact, the mysterious liquefying of the blood relic has rarely occurred outside the “canonical” date. The dried blood of St. Gennaro, which is preserved in two glass phials in the Naples Cathedral, traditionally liquefies three times a year: on the saint’s September 19 feast, which commemorates his martyrdom in the Catholic liturgical calendar; December 16, the date of the eruption of Mt. Vesuvius in 1631, which was believed to have been halted through the saint’s intervention; and the Saturday before the first Sunday in May.

St. Gennaro was bishop of Naples and is a saint and martyr of the Roman Catholic and Eastern Orthodox Churches. Historical sources claim he was martyred in the year 305 during the Diocletian persecution.

According to legend, St. Gennaro’s blood was saved by a woman called Eusebia just after his death. The practice of gathering blood for relics was a common practice beginning in the days of persecution when the early Christians soaked cloths in the blood shed by martyrs or, if possible, actually collected the liquid in flasks to keep as devotional items. In the catacombs these flasks were buried with the dead. Their discovery indicated that the person had died a martyr.

After his meeting with priests and consecrated religious in the Naples cathedral, Pope Francis will greet the sick in the Basilica of Gesù, followed by a meeting with young people on the Caracciolo sea-front.

Diane Montagna is Rome correspondent for Aleteia’s English edition.