Actress Juliette Binoche and fellow French environmentalists received encouragement from Pope Francis at a private Vatican meeting Thursday, where the pontiff confessed he did not understand more than a decade ago his fellow churchmens’ worries about the Amazon.

While he was still archbishop of Buenos Aires, “I didn’t understand anything” about ecology problems, he told the activists in improvised remarks.

″(Then) I followed a path of conversion, of understanding the ecological problem” of the Amazon’s exploitation, Francis said.

Francis’ understanding grew and formed the basis of his 2015 encyclical that called for urgent action to protect the Earth’s environment. He said he consulted with scientists and theologians, who helped with a first draft of the landmark document.

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“We must work so that everyone goes down the path of ecological conversion,” Francis told his guests.

Francis now has made championing the cause of the environment a major plank of his papacy, especially noting how people living on life’s margins are often most adversely impacted by pollution or exploitation of natural resources.

Recalling his 2018 pilgrimage in Peru, which took him to the Amazon, Francis spoke about how he dined with 14 indigenous leaders and then came away impressed with their wisdom and how they “live in harmony with Creation.”

In his prepared speech, Francis said the urgency to committing oneself to the cause of healing the environment was made plain by the COVID-19 pandemic.

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“We understand to what point we are tied one to the other, inserted in a world whose future we share, and that maltreating it can’t help but bring grave consequences, not only environmental but social and human.”

Binoche and the other activists work with the French Conference of Bishops on environmental themes. In 2018, Binoche was an author of a letter calling on all politicians to act decisively in tackling climate change.

Francis said he was heartened that consciences were being raised.

“While the conditions of the planet can appear catastrophic, and certain situations appear even irreversible, we Christians cannot lose hope,” Francis said.