Pope Francis looks on during a penitential ceremony on March 4 at St. Peter's Basilica in Vatican City. Francis has imposed new financial rules on those working to promote the canonization of potential saints. Tiziana Fabi/AFP/Getty Images hide caption

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Polish nuns do most of the cooking at the Vatican. Here, they prepare sweets for the Feast of St. Nicholas. Katarzyna Artymiak/Courtesy of Sophia Institute Press hide caption

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Peter Saunders, a British advocate for survivors of sexual abuse by priests, in Rome on Saturday. Saunders is a high-profile abuse survivor and critic of the Vatican — and until Saturday, was a member of Pope Francis' sex abuse advisory commission. Gregorio Borgia/AP hide caption

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The closing ceremony of the Second Vatican Council in St. Peter Square on Dec. 9, 1965. Forty bishops pledged to forsake worldly goods, but the agreement was largely ignored. Pope Francis' emphasis on helping the poor has revived talk about the Pact of the Catacombs. Keystone-France/Gamma-Keystone via Getty Images hide caption

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Pope Francis' Emphasis On Poverty Revives The 'Pact of The Catacombs'

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Journalists Emiliano Fittipaldi, left, and Gianluigi Nuzzi face criminal charges, along with three former Vatican officials. They're seen here at events publicizing their new books about financial dealings in the Catholic Church. AP hide caption

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The balconies of St. Peter's at the Vatican in Rome. The two people arrested Monday were members of a committee convened by Pope Francis in 2013 to keep him abreast of financial reforms in the Vatican government. Giuseppe Ciccia/Barcroft Media /Landov hide caption

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Vatican spokesman Rev. Federico Lombardi (right) is denying claims in Italian newspapers that Pope Francis has a benign brain tumor. The rumors are part of an attempt to undermine the pope, the Vatican says. Andrew Medichini/AP hide caption

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Pope Francis is greeted by President Obama after arriving outside Washington, D.C., on Tuesday. Chip Somodevilla/Getty Images hide caption

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The Complicated History Of Popes And U.S. Presidents

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