ROME – On Sunday Pope Francis descended beneath St. Peter’s Basilica into the Vatican Grottoes, where many popes are laid to rest, after a Mass was said in honor of Blessed Pope Paul VI on the 39th anniversary of his death.

The Mass was presided over by the Bishop of Albano, Marcello Semeraro, since the late pope actually died in his diocese, at the papal summer estate of Castel Gandolfo.

The Mass also celebrated the feast of Transfiguration, when the apostles Peter, James and John witnessed the radiance of Jesus with the prophets Moses and Elijah, which Semeraro said during the homily, “reminds us of the ascension to the Heavens of blessed Paul VI, whose body lies in these grottoes.”

Pope Francis approved Paul’s beatification in October 2014 and there has been speculation that Francis might dispense with the requirement of a second miracle to declare Paul a saint, technically known as an “equipollent” canonization, as he did with John XXIII, the other pope of the Second Vatican Council (1962-65).

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The Mass used to take place at Castel Gandolfo before Paul’s beatification, but now that the official feast has been moved to September 26, Semeraro celebrates this occasion at the Vatican with those who knew him well.

“Paul VI held friendship in high esteem,” the bishop said. “The friendship with God, first of all,” he added, “but also human friendship,” which he considered “‘a gradual exercise that leads us to the love of God.’”

In his homily, Semeraro also quoted Paul’s document ‘Thoughts on Death,’ defining it as “a high and profound witness.”

“Walk while you have light,” the blessed pope had written in his document. “I would like, in the end, to be in the light.”

Biographers define Paul VI as the ‘pope of light’ and the feast of Transfiguration is a perfect time to commemorate his legacy. Paul VI imagined that the event took place “in the dark of night so that the three who were asleep were awoken by a bright ray of light,” Semeraro said.

“It’s not only an enveloping light, but also a talking light so that the vision soon becomes audible. The voice of the Father while underlying the divine nature of Christ, reiterates the necessity of listening to him,” the bishop added.

“It is necessary to listen to Jesus because the voice of the Law and the language of the Prophets are in him,” he said.

At the end of the Mass, Pope Francis and Semeraro, who is also the Secretary of the council of nine high-ranking prelates who help the pope run the Catholic Church, went before Paul VI’s tomb to pray and pay their respects.

This year also celebrates another important anniversary relative to Paul VI’s legacy: The 50th anniversary of his encyclical Populorum Progressio (“On the Progress of Peoples”), which Francis praised for its “felicitous” explanation of integral development as “development of each man and of the whole man.”

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The encyclical was used as the blueprint for the creation of the Dicastery for Integral Human Development, a Vatican department focused on promoting peace and development created by Pope Francis as part of his Church reform.

It was Paul VI “who explained in detail the meaning of ‘integral development’,” Francis told bishops and scholars who convened in April for a conference on the late pope’s encyclical.

“Our duty to solidarity obliges us to search for the right methods for sharing, so that there no longer be the dramatic separation between those who have too much and those who have nothing, between those who throw away and those who are thrown away. Only a path of integration among peoples can allow humanity to have a future of hope and peace.”

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