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.
Pope Francis accepts a letter from a child he visited at a pediatric hospital in Rome on Thursday, December 15, 2016.
Pope Francis poses with members of the International Catholic Rural Association at the Vatican on Saturday, December 10, 2016.
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.
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.
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.
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.
Pope Francis confesses in St. Peter's Basilica during the Vatican's Penitential Celebration on Friday, March 4, 2016.
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 ear