Fourteen years ago, the darker impulses of religion unleashed a war on New York City and the Western world.
Friday, a son of Italian immigrants, born in a Buenos Aires barrio, who has ascended to the role of a spiritual global shepherd, stood at the lower Manhattan grounds of so much carnage -- a peace-seeking example of religion's appeal to light.
Silence, punctuated only by cascading water, the occasional click of a camera or a child's cry, fell on Ground Zero as Pope Francis fixed his gaze on an avalanche of names etched in bronze.
It was one of many snapshots of poignancy as Francis joined other spiritual leaders at the National September 11 Memorial & Museum -- a rare moment of sadness and solemnity on the pontiff's otherwise joyous visit to New York City.
On a stage set up inside the memorial museum, the pope talked of a grief one could feel but no words could describe.
"Here grief is palpable," the pope said in his late-morning remarks.
As he spoke, an audience including family members of those lost on Sept. 11, 2001, survivors, and first responders who raced to the rubble after the terror attacks, listened intently.
Joining the pontiff: clergy representing Islam, Hinduism, Buddhism, evangelical Christians, the Greek Orthodox Church and Judaism -- the denomination that gave rise to his own.
"The water we see flowing toward that empty pit reminds us of all those lives which fell prey to those who think that destruction, tearing down, is the only way to settle conflicts," Francis said.
He spoke of the "unspeakable violence" set loose when the planes hit and 2,753 people lost their lives, and of the "hallowed ground" under his feet.
To his right stood the last upright beam from the wreckage of the World Trade Center. It bears the rough lettering designating the units of the FDNY and other first responders.
The pope was there to mourn with the others, but his mission at Ground Zero had a broader goal: an ecumenical prayer of solace and love for a city and a world still recovering from the acts of 19 hijackers more than a decade past.
"It is a source of great hope that in this place of sorrow and remembrance I can join with leaders representing the many religious traditions which enrich the life of this great city," the pope said. "I trust that our presence together will be a powerful sign of our shared desire to be a force for reconciliation, peace and justice in this community and throughout the world."
Before the pope arrived, sidewalks interlocking the black granite pools where the towers stood, filled with onlookers.
Joan Higgins, 82, of Freeport, was among those who came to glimpse the pope and gain something else.
Her son, Timothy Higgins of Farmingville, died in the attacks. An FDNY lieutenant, he was married with three children.
"I really would like to see the pope and get his blessing," she said. "I'm a very devout Catholic and I believe that he would pray for Tim's soul and give his blessings."
As at other events on the pope's itinerary in Manhattan, Cardinal Timothy Dolan, the archbishop of New York, stayed close by the pontiff at Ground Zero.
The two leaders, peers as cardinals until Francis' papal election in 2013, walked along the border of one of the pools. The pope stopped and gently rested a rose on a bronze surface covered with names of the dead.
Inside the museum, the pope met victims' families, including some from Long Island.
Among them were relatives of Jonathan Lee Ielpi, 29, of Great Neck, an FDNY firefighter, and Michael Patrick Iken, 37, of the Bronx, who worked at Euro Brokers and grew up in Massapequa.
Former Mayor Michael Bloomberg, chairman of the Memorial & Museum, introduced families to the pope.
Dolan welcomed Francis to the service, entitled "A Witness to Peace."
The jovial cardinal injected humor into the proceedings by explaining his interfaith outreach -- evidenced by many listening -- as both a confession and a bit of a teasing boast.
"We in New York are sinners . . . but one of the things we do well is sincere and fruitful interreligious friendship."
Rabbi Elliot Cosgrove of Park Avenue Synagogue and other clergy spoke of the attacks as a mission of terror with the goal of using religion to justify a horrific act.
"In this place, where horrendous violence was committed falsely in the name of God, we, representatives of the world religions in this great City of New York, gather to offer words of comfort and prayer," Cosgrove said.
Iman Khalid Latif, the executive director and chaplain of the Islamic Center at New York University, told the pope and others that "intolerance and ignorance fueled those who attacked this place."
He said unlike those out to destroy religious freedom, "we stand together as brothers and sisters to condemn their horrific acts of violence and honor each life that was lost unconditionally."
The pope later toured the museum's extensive exhibit.
A copy of the New Testament recovered from the towers' wreckage caught the pontiff's attention. He found the page containing advice from Jesus to his followers to reject violence as revenge and instead turn the other cheek.
It was all more than enough to move the Rev. Wilfred Tyrrell, a Brentwood native and a member of the Franciscan Friars of the Atonement in upstate Graymoor.
"It was just the collective energy of the spirit at work," Tyrrell said, "a message of peace, shalom and salaam."
With Bart Jones
and William Murphy