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ON BOARD THE PAPAL PLANE – Pope Francis on his way back to Rome on Monday criticized the rise of western populism, advocated on behalf of migrants, and stressed the need to continue working for unity with the Orthodox. 

Speaking to journalists on board his flight from Athens to Rome at the end of a Dec. 2-6 visit to Cyprus and Greece, the pope also touched on the fall from grace of French Archbishop Michel Aupetit, the former archbishop of Paris. 

Aupetit’s resignation was accepted on Thursday after a report was published last week in Le Point magazine saying he had a consensual, intimate relationship with a woman.

Aupetit responded to the report saying he didn’t have sexual relations with the woman. However, in an interview with Catholic radio Notre Dame last week, the French archbishop admitted that he “poorly handled the situation with a person who was in contact many times with me.”

Francis challenged allegations against Aupetit, saying, “what did Aupetit do that was so bad in order to give his resignation?”

“Answer me,” he asked the journalists on the papal plane, and handed the microphone to the journalist who asked the question. When there was no answer, the pope insisted that “if we don’t know the accusation, we can’t condemn him.”

When there are allegations, an investigation must be made, but it should not be the public that condemns, Francis said.

Pope Francis admitted that while there was perhaps a violation of the sixth commandment not to commit adultery, it was “not totally” a violation in Aupetit’s case.

There were “small caresses, massages…This is the accusation,” he said, saying “This is a sin, but it’s not among the most serious, no?”

Everyone is a sinner, including Aupetit and himself, the pope said, noting that even Peter sinned by rejecting Jesus before his passion.

“We must all always feel that we are sinners, and we must be humble,” he said.

“When gossip grows and grows and grows and takes the good name from someone…This is an injustice,” he said, saying he accepted Aupetit’s resignation “not on the altar of truth, but on the altar of hypocrisy.”

In Aupetit’s case, Pope Francis appeared to deviate from his previous approach to similar situations, having refused to accept the resignation of German Cardinal Reinhard Marx earlier this year over failure to properly handle the clerical abuse crisis.

 Pope Francis also reiterated criticisms he made during his opening speech in Greece to civil authorities, when he said that democracy throughout Europe and the West is being weakened by a wave of nationalism.

The pope told the reporters on the plane that democracy is “a treasure of civilization. A treasure that countries need to defend with themselves but also elsewhere.”

Francis said he sees two current threats to democracy, the first of which is populism, which he said “is starting to show its nails.”

“I am thinking of the populism from last century: Nazism. Nazism was a populism that defended national values. Or so it said. But it managed to annihilate democratic life, it became a dictatorship,” he said, cautioning governments on both the right and left to be careful “not to slip on the road of populism.”

Populism, he said, “has nothing to do with popularism, which is the expression of a nation’s identity, folklore, value,” but is rather a system in which national values are sacrificed and watered-down “in favor of a government that goes beyond national interests.”

“We shouldn’t water down our identity for national gain,” he said, pointing to the 1907 end times novel The Lord of the World, written by English convert Father Robert Hugh  Benson, who foresaw the rise of an international government that ruled all other nations.

“This is what happens when a superpower dictates the economic, cultural and social value,” he said.

Pope Francis also touched again on the issue of migration, which was a primary theme of his visit to both Cyprus and Greece, telling journalists that those who build walls “forget history.”

He also spoke of relations with the Orthodox churches, saying they can walk together toward unity through prayer and acts of charity, while theological disputes are worked out over time. He also said a potential second meeting with Russian Orthodox Patriarch Kirill of Moscow is being planned, but offered no other details.

Follow Elise Ann Allen on Twitter: @eliseannallen