Colombian President Juan Manuel Santos, left, reads aloud words engraved on a pen as he meets with Pope Francis at the Vatican, Friday, December 16, 2016. The words "The bullets have written our past, education will write our future" are engraved on the pen, made from a recycled bullet once used in the civil war between the Colombian government and the Revolutionary Armed Forces of Colombia (FARC). The pen was later used to sign the peace agreements between the parties earlier this year. Santos, who was awarded the 2016 Nobel Peace Prize for his efforts to end the region's longest-running conflict, presented Pope Francis with the pen.
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Pope Francis accepts a letter from a child he visited at a pediatric hospital in Rome on Thursday, December 15, 2016.
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Pope Francis poses with members of the International Catholic Rural Association at the Vatican on Saturday, December 10, 2016.
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Pope Francis salutes the faithful upon his arrival in St. Peter's Square at the Vatican for the Special Jubilee Papal Audience on Saturday, October 22, 2016.
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Pope Francis looks on with joy as he releases a dove as a symbol of peace during a meeting with the Assyrian Chaldean community at the Catholic Chaldean Church of St. Simon Bar Sabbae in Tbilisi, Georgia, on September 30, 2016.
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Pope Francis passes the main entrance to Auschwitz-Birkenau, the former concentration camp in Poland, on Friday, July 29, 2016. The Pope was there to pay tribute to those who died in the Holocaust.
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Pope Francis looks on as Catholicos of All Armenians Karekin II celebrates the Divine Liturgy at the Apostolic Cathedral in Etchmiadzin, outside Yerevan, Armenia, on June 26, 2016.
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Pope Francis arrives to celebrate an extraordinary Jubilee Audience as part of ongoing celebrations of the Holy Year of Mercy in St. Peter's Square in Vatican City on May 14, 2016.
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Pope Francis hugs a child at the Moria refugee camp on the Greek island of Lesbos on Saturday, April 16, 2016. Pope Francis received an emotional welcome on the island during a visit showing solidarity with migrants fleeing war and poverty.
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Pope Francis confesses in St. Peter's Basilica during the Vatican's Penitential Celebration on Friday, March 4, 2016.
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Pope Francis tries on a traditional sombrero he received as a gift from a Mexican journalist on Friday, February 12, 2016, aboard a flight from Rome to Havana, Cuba. The voyage kicked off his weeklong trip to Mexico. With his penchant for crowd-pleasing and spontaneous acts of compassion, Pope Francis has earned high praise from fellow Catholics and others since he succeeded Pope Benedict XVI in March 2013.
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Pope Francis arrives for his visit with prisoners in Santa Cruz, Bolivia, on Friday, July 10, 2015. The Pope emphasized the plight of the poor during his eight-day tour of South America, which also included stops in Ecuador and Paraguay.
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Bolivian President Evo Morales presents the Pope with a gift of a crucifix carved into a wooden hammer and sickle -- the Communist symbol uniting laborers and peasants -- in La Paz, Bolivia, on Wednesday, July 8, 2015.
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Pope Francis greets a crowd of Italian Catholic boy scouts and girl guides at St. Peter's Square on Saturday, June 13, 2015.
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Russian President Vladimir Putin, left, meets Pope Francis at the Vatican on Wednesday, June 10, 2015. The Pope gave Putin a medallion depicting the angel of peace, Vatican spokesman Federico Lombardi said. The Vatican called it "an invitation to build a world of solidarity and peace founded on justice." Lombardi said the pontiff and President talked for 50 minutes about the crisis in Ukraine and violence in Iraq and Syria.
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Pope Francis meets with Cuban President Raul Castro at the Vatican on Sunday, May 10, 2015. Castro thanked the Pope for his role in brokering the rapprochement between Havana and Washington.
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The Pope prays face down on the floor of St. Peter's Basilica during Good Friday celebrations at the Vatican on Friday, April 3, 2015.
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Pope Francis touches a child's face as he arrives for a meeting at the Vatican on Friday, March 6, 2015.
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Hindu priest Kurukkal SivaSri T. Mahadeva presents a shawl to Pope Francis in Colombo, Sri Lanka, on Tuesday, January 13, 2015.
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The Pope attends Christmas Eve Mass at St. Peter's Basilica in Vatican City in December 2014.
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Pope Francis and Ecumenical Patriarch Bartholomew I address the faithful in Istanbul on Sunday, November 30, 2014.
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Pope Francis speaks during the feast-day Mass while on a one-day trip to Italy's Calabria region in June 2014. The Pope spoke out against the Mafia's "adoration of evil and contempt for the common good," and declared that "Mafiosi are excommunicated, not in communion with God."
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Pope Francis prays next to a rabbi at the Western Wall in Jerusalem's Old City in May 2014. The Pope went on a three-day trip to the Holy Land, and he was accompanied by Jewish and Muslim leaders from his home country of Argentina.
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The Pope meets the faithful as he visits the Roman Parish of San Gregorio Magno in April 2014.
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Queen Elizabeth II and Prince Philip, Duke of Edinburgh, have an audience with the Pope during their one-day visit to Rome in April 2014.
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Francis speaks with US President Barack Obama at the Vatican in March 2014.
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The Pope blesses the altar at Rome's Basilica of Santa Sabina as he celebrates Mass on Ash Wednesday in March 2014.
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Daniele De Sanctis, a 19-month-old dressed as the pope, is handed to Francis as the pontiff is driven through the crowd in St. Peter's Square in February 2014.
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Wind blows the papal skullcap off Pope Francis' head in February 2014.
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A lamb is placed around Francis' neck in January 2014 as he visits a living nativity scene staged at a church on the outskirts of Rome.
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Pope Francis meets with Pope Emeritus Benedict XVI at the Vatican in December 2013. Benedict surprised the world by resigning "because of advanced age." It was the first time a pope has stepped down in nearly 600 years.
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Pope Francis marked his 77th birthday in December 2013 by hosting homeless men at a Mass and a meal at the Vatican. One of the men brought his dog.
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Pope Francis embraced Vinicio Riva, a disfigured man who suffers from a non-infectious genetic disease, during a public audience at the Vatican in November 2013. Riva then buried his head in the Pope's chest.
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Pope Francis jokes in November 2013 with members of the Rainbow Association Marco Iagulli Onlus, which uses clown therapy in hospitals, nursing homes and orphanages.
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A young boy hugs Francis as he delivers a speech in St. Peter's Square in October 2013. The boy, part of a group of children sitting around the stage, played around the Pope as the Pope continued his speech and occasionally patted the boy's head.
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Francis has eschewed fancy cars. Here, Father Don Renzo Zocca, second from right, offers his white Renault 4L to the Pope during a meeting at the Vatican in September 2013.
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Francis has his picture taken inside St. Peter's Basilica with youths who came to Rome for a pilgrimage in August 2013.
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During an impromptu news conference in July 2013, while on a plane from Brazil to Rome, the Pope said about gay priests, "Who am I to judge?" Many saw the move as the opening of a more tolerant era in the Catholic Church.
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Crowds swarm the Pope as he makes his way through World Youth Day in Rio de Janeiro in July 2013. According to the Vatican, 1 million people turned out to see the Pope.
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Francis frees a dove in May 2013 during his weekly general audience in St. Peter's Square.
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Francis embraces a young boy with cerebral palsy in March 2013 -- a gesture that many took as a heartwarming token of the Pope's self-stated desire to "be close to the people."
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The Pope washes the feet of juvenile offenders, including Muslim women, as part of Holy Thursday rituals in March 2013. The act commemorates Jesus' washing of the Apostles' feet during the Last Supper.
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Francis stands at the reception desk of the Domus Internationalis Paulus VI residence on March 14, 2013, where he paid the bill for his stay during the conclave that would elect him leader of the world's 1.2 billion Catholics.
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Francis, formerly known as Argentine Cardinal Jorge Mario Bergoglio, was elected the Roman Catholic Church's 266th Pope in March 2013. The first pontiff from Latin America was also the first to take the name Francis.
