According to tradition, the Blessed Mother revealed the Rosary to St. Dominic as the threats of error and falsehood propagated by the Albigensian heresy grew. That and several other episodes in the history of the Church have illustrated that the Rosary is most definitely a spiritual weapon to be used to defeat what is false and evil in the world.

Blessed Bartolo Longo found that out firsthand in his late 20s when introduced to the Rosary. Having grown up Catholic, Longo grew away from the Faith in his young adult years and gave into the pressures of the culture.

Back then, the Church became the target of various attacks because the pope maintained a certain portion of the territory that is now Italy. Although the pope eventually lost it — removing any political power from the papacy after nearly a millennium — Italy saw his attempts to maintain control as something akin to an enemy of the state.

Unification was en vogue as Italy was being formed from various disparate territories. As a young law student, Longo joined that cause.

Later Longo was swept into another cultural trend: experimenting with spiritualism, particularly the occult and satanic worship. He found himself involved so much in a satanic cult that he claimed he was eventually ordained a priest of Satan.

That changed when he was introduced to the power of the Rosary by a Dominican priest. Longo had become acquainted with the priest through a boyhood friend who convinced him to leave Satanism. He had confided in that friend how his life was filled with anxiety; he was depressed and confused.

For the rest of his life he would go on unceasingly to work to foster devotion to the Rosary, leading to his renown as “a true apostle of the Rosary” as Pope St. John Paul II called him in a 2002 apostolic letter on the Rosary (Rosarium Virginis Mariae, No. 8).

Why did the Rosary have such a major impact on Longo? By his own admission, the depression and anxiety by which he found himself plagued eventually led to thoughts of suicide. He was successful in rejecting the temptation by recalling one of the promises held by tradition that Our Lady made to St. Dominic about the Rosary: “He who propagates my Rosary will be saved.” He believed the Rosary saved his life, and he knew it could do the same for others.

All the while, Longo had kept up the practice of law. He eventually came to Pompeii, Italy — site of the ancient volcanic eruption — and took up work for a young, widowed Countess Mariana De Fusco. The darkness she experienced at the time of her husband’s death was brightened by a renewed and deepened prayer life. It was at this time, around the time of Longo’s conversion, that he met Countess De Fusco.

The two began to collaborate on a project to bring about greater devotion to the Rosary. They established a shrine at an old, deteriorating church in Pompeii. Longo repaired it and established a confraternity of the Rosary. Each year a festival would be held at the shrine.

Over the years, miracles allegedly began to occur at the shrine. The shrine was consecrated by a delegate of Pope Leo XIII in 1879.

The same pope convinced the countess and Longo to marry in 1885. They remained celibate in their marriage. Theirs was a marriage of spiritual parenthood where they cared for the spiritual and material needs of the poor and disadvantaged.

Together they cared for orphans and gave assistance to the imprisoned — most of all they continued promoting the Rosary, even after donating the Pompeii shrine to the Holy See in 1906.

His feast day is Oct. 5.

Michael R. Heinlein is editor of Simply Catholic. Follow him on Twitter at @HeinleinMichael.