VATICAN CITY (AP) -- Pope Francis on Tuesday pushes open the huge bronze Holy Door of St. Peter's Basilica to formally launch his yearlong "revolution of tenderness" amid unprecedented security aimed at thwarting the threat of a Paris-style attack at the Vatican.
Hundreds of extra police, carabinieri and soldiers have been deployed around Rome, and a no-fly zone imposed on its skies, to protect the projected 10 million Catholic pilgrims who over the next year will flock to Rome on foot, by car, train and plane to take part in Francis' Holy Year of Mercy.
Francis launched the 12-month jubilee to emphasize what has become the leitmotif of his papacy: to show the merciful and welcoming side of a Catholic Church more often known for its moralizing and judgment.
With Emeritus Pope Benedict XVI on hand, Francis on Tuesday morning will celebrate the evocative Holy Year ritual, opening the Holy Door and walking through it to symbolize the pilgrimage of life's journey and the sacrifices that must be endured.
On Tuesday night, the Vatican will lend itself to another one of Francis' leitmotifs, environmental protection. A coalition of humanitarian groups has banded together to screen images of nature by well-known photographers and filmmakers on the facade of St. Peter's.
Ahead of the big day, police patrolled St. Peter's Square as the first of an estimated 100,000 people expected for Tuesday's Mass arrived to collect their pilgrim packets.
"It's normal that security checks are increased because of the latest terrorist attacks," said Maria Di Palo, a pilgrim from Naples. "We hope the pilgrims will cooperate as well, and that they won't complain."
Holy Years are generally celebrated every 25-50 years, and over the centuries they have been used to encourage the faithful to make pilgrimages to Rome to obtain an "indulgence" -- the ancient church tradition related to the forgiveness of sins that roughly amounts to a "get out of Purgatory free" card. Unlike in Martin Luther's time, these indulgences are free and available to those who pass through the Holy Door.
The last Holy Year was in 2000, when St. John Paul II ushered in the church's third millennium and some 25 million pilgrims flocked to a Rome that had undergone a multi-million dollar facelift for the occasion.
In typical Francis fashion, the pope made clear from the start that he wanted this Holy Year to be a more sober occasion. For the first time, the pope instructed all cathedrals around the world to open their Holy Doors to pilgrims to encourage the faithful to mark the jubilee at home rather than coming to Rome.
Nevertheless, Italian officials seized on the excuse of the jubilee to allocate millions of euros for dozens of public works projects around the capital, practically none of which has been completed.
The Vatican's lead organizer for the jubilee, Archbishop Renato Fisichella, lamented last week that the Vatican had essentially wasted four months of planning time thanks to a local political scandal that resulted in Rome's mayor being ousted midway through the jubilee preparations. Fisichella said all the Vatican wanted were refurbished sidewalks leading to St. Peter's to make sure pilgrims don't trip on potholes or crooked cobblestones. Several of those streets remain closed as construction work continues.
Francis announced his Holy Year on the second anniversary of his papacy, saying his aim was "to give comfort to every man and every woman of our time." It was in keeping with his priority to make the church a "field hospital" for injured souls, where the wounded are welcomed and loved, not judged.
The jubilee year will feature a host of special Masses and extra general audiences to accommodate the throngs of pilgrims, while Francis himself has set aside one Friday each month to slip out of the Vatican to perform an act of mercy himself, in private.
In keeping with his aim to make the sacrament of confession more readily accessible during the Holy Year, Francis in September announced that all priests around the world could absolve women of the sin of abortion, usually reserved to bishops. He also allowed priests of the schismatic Society of St. Pius X, who have no legal status in the church, to hear confessions. And he appointed 800 "missionaries of mercy" -- a roving band of priests who can absolve people of the five sins that are "reserved" to the Holy See, including desecrating the Eucharist and breaking the confessional seal.
For all the pomp of Tuesday's ceremony, Francis technically launched the Holy Year of Mercy last week in Central Africa Republic, when he pushed open the Holy Door of the Bangui cathedral. His aim was to give the conflict-weary Christians there a spiritual boost, and show the universality of his message of mercy.
Elsewhere around the world, Holy Doors will be opening at cathedrals starting this Sunday.
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