St. Januarius is said to have been born in Naples and to have been bishop of Beneventum (just east of Naples), who, with his companions, suffered martyrdom in the persecution of Diocletian at Naples in 303. They were first thrown to the lions in the arena, but none of the beasts would attack them, so they were beheaded. The Christian women collected the blood of St. Januarius in a glass vial and placed it in his tomb.
St. Januarius has been invoked against volcanic blasts since 1631, when a violent eruption of Mount Vesuvius threatened Naples. The people of the city prayed to him to help them, and the flow of lava stopped. But the enduring fervor for this saint of the volcanoes is rooted in an inexplicable event known as “the miracle of the liquefaction.”
The main patron saint of Naples, St. Januarius is celebrated there on three feast days each year. The blood is made to "work" six times on each of these three days. It consists of a dark solid mass and is held in a glass vial kept in the treasury chapel of Naples cathedral. The vial is brought out with a reliquary said to contain the saint's skull. It is then held and turned by a priest as the people pray. After a period of anything from two minutes to an hour, it appears to become red and to bubble - or not. At the moment the solid mass becomes liquid, the priest holds up the relic, turning it this way and that so the crowd can see the liquid sloshing around inside the vial. With the cry, “The miracle has happened!” everyone in the church surges forward to kiss the relic and all sing the "Te Deum" in thanksgiving.
Attempts have been made to find a scientific explanation why something solid should suddenly liquefy, but none of them have been satisfactory. There have been times when the blood did not liquefy, which the people take as a warning from the saint or a sign of his displeasure. The relic remained solid the year Naples elected a Communist mayor, but liquefied spontaneously when the late Cardinal Terence Cooke of New York visited the shrine of St. Januarius in 1978.