ROME — Pope Francis praised the actions of young climate change activists like Greta Thunberg Thursday, saying they remind people of the urgent need for “ecological conversion.”

Young people “have much to offer, thanks to their enthusiasm and commitment, to say nothing of their thirst for truth, the pontiff told diplomats gathered in the Vatican for his annual speech to the corps.

“We have seen this in the way many young people have become active in calling the attention of political leaders to the issue of climate change,” he said.

Environmental action “ought to be a concern of everyone and not the object of ideological conflict between different views of reality or, much less, between generations,” the pope declared. “The protection of the home given to us by the Creator cannot be neglected or reduced to an elitist concern.”

“Young people are telling us that this cannot be the case, for at every level we are being urgently challenged to protect our common home and to bring the whole human family together to seek a sustainable and integral development,” he continued.

“They remind us of the urgent need for an ecological conversion, which must be understood in an integral way, as a transformation of how we relate to our sisters and brothers, to other living beings, to creation in all its rich variety and to the Creator who is the origin and source of all life,” he said.

The pope went on to express his displeasure over the failure of the recent COP25 climate conference to make further commitments to curb greenhouse gas emissions.

“Sadly, the urgency of this ecological conversion seems not to have been grasped by international politics, where the response to the problems raised by global issues such as climate change remains very weak and a source of grave concern,” he said.

The U.N. Framework Convention on Climate Change (COP25) “raises serious concern about the will of the international community to confront with wisdom and effectiveness the phenomenon of global warming,” he said, “which demands a collective response capable of placing the common good over particular interests.”

In his message to the participants in the COP25 United Nations convention, the pope had already pointed hopefully to young people as the vanguard of the battle against climate change.

“Young people today show a heightened sensitivity to the complex problems that arise from this ‘emergency,’” Francis said. “We must not place the burden on the next generations to take on the problems caused by the previous ones.”

Last August, the pope said he was greatly encouraged by the involvement of young people in the battle against climate change, which he called a “global emergency” that can lead to “the death of humanity.”

There are signs of hope for the environment “especially in the movements of young ecologists, such as the one led by Greta Thunberg, ‘Fridays for Future.’” Francis said.

“I saw one of their signs that struck me: ‘We are the future!’” he said.

The pope had met the young Swedish activist in the Vatican last April and urged her to continue her crusade against climate change.

This past December, Cardinal Peter Turkson, prefect of the Vatican’s office for the Promotion of Integral Human Development, similarly praised Greta Thunberg as “a great witness to Church teaching on care for the environment.”

“What is her objective? Skipping school for a future, a future that can’t be guaranteed because there is no care for the environment,” the 71-year-old cardinal said.

Just after Christmas, the Irish primate, Archbishop Eamon Martin of Armagh, denounced critics of the 16-year-old and lauded her for “speaking prophetically to the world.”

“I can’t understand why people would choose to attack Greta Thunberg,” the archbishop said. “She is passionate about what she believes; she is only a young girl and she is speaking prophetically to the world and what do we do? We attack her. We attack her message.”

“In fact, there are a lot of deniers who believe that this is all made up and yet we see the reality of climate change and we know scientists are absolutely unanimous in telling us that human behaviour is at least aggravating the problem,” he said.

While many prelates have joined the ranks of celebrities and political leaders in their adulation of the young climate activist, several have stuck out from the crowd with a more critical view.

On Christmas Eve, Krakow Archbishop Marek Jedraszewski gave an interview to Poland’s TV Republika in which he said that the Christian tradition is undermined by new movements such as “ecologism,” which seeks “to impose itself as a binding doctrine,” and threatens the Christian understanding of man’s place in creation.

This ecologism is “a very dangerous phenomenon because it’s not just that a teenager is trying to impose it, but that this activist is becoming an oracle for all political and social forces,” he continued, in reference to Ms. Thunberg.

Angry complaints rained down on the prelate for having dared to call into question the prophetic charism of Thunberg, to which fifteen other Polish bishops responded with an open letter expressing support for Jedraszewski.

“We stand in solidarity with you against these hurtful attacks, which an evangelical defender of truth must bear,” they wrote. “It is always praiseworthy to stand up for Christian anthropology, which sees in man the image of God himself, so we assure you of brotherly prayer and unity.”

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