Pope Francis' forthcoming encyclical on the environment has been described as "long-awaited" and "much-anticipated." Indeed, as Peter Smith, who covers religion for the Pittsburgh Post-Gazette, recently put it: "Rarely in modern times has a major papal pronouncement received so much attention and debate before it’s even been delivered." And why not? In addition to being Francis' first encyclical, it will be the first encyclical on the environment in the history of the Roman Catholic Church.

The landmark document is expected to be issued sometime this summer, and perhaps even later this month, with the title "Laudato Sii" ("Praised Be You"), taken from the pope's namesake St. Francis of Assisi’s Canticle of the Sun, which praises God for creation, and the subtitle "Sulla cura della casa commune" (“On the care of the common home”). Published around the year 1224, St. Francis’ prayer reads: “Be praised, my Lord, through all Your creatures, especially through my lord Brother Sun,” and continues to praise God for “Sister Moon,” “Brothers Wind and Air,” “Sister Water,” “Brother Fire, and “Mother Earth.”

In a speech he delivered in Ireland in March, Cardinal Peter Turkson of Ghana, the president of the Pontifical Council for Justice and Peace, which prepared the first draft of the encyclical, said that Laudato Sii "will explore the relationship between care for creation, integral human development and concern for the poor.”

The pope means business

A papal letter sent to all the bishops of the Roman Catholic Church, an encyclical is the second most important type of document issued by popes, after an Apostolic Constitution. Its content carries significant weight, even beyond the church itself. In 1950, Pope Pius XII wrote about the authority of encyclicals in one of his own, Humani generis: "If the Supreme Pontiffs in their official documents purposely pass judgment on a matter up to that time under dispute, it is obvious that that matter, according to the mind and will of the Pontiffs, cannot be any longer considered a question open to discussion among theologians."

Unsurprisingly, popes have used them to help clarify the church's position on a wide range of controversial issues, from birth control and contraception (Pius X), to the Soviet invasion of Hungary (Pius XII) and the Vietnam War (Paul VI). Even before its release, Francis' encyclical is already stirring controversy in the hotly debated arena of climate change.

Amid detractors, reframing the climate debate

While environmentalists are hopeful about the papal message, resistance has been building. The Heartland Institute, a leading American think tank for climate change skeptics, sent a contingency to Rome last month during a U.N.-Vatican summit as a "prebuttal" to the encyclical. “We’re here to prevent the pope from making the mistake of having the U.N. as an advisor, because he won't be getting the whole picture,” Heartland spokesman Jim Lakely said. He defined global warming as “the combination of abandoning the scientific method to analyze climate change, stacking the deck in favor of climate alarmism, and frankly, outright corruption.”

GOP presidential hopeful Rick Santorum wants the pope to refrain from engaging in the climate change debate, saying the pontiff should "leave science to the scientists." (Francis actually earned a secondary diploma in chemistry from a technical college in Argentina and worked as a chemist before entering the seminary.) In addition, pro-lifers are concerned that the encyclical will be a backdoor entry to population control, which some environmentalists see as a potent mechanism to save a planet with dwindling resources and a skyrocketing number of humans. “The road the church is heading down is precisely this: To quietly approve population control while talking about something else," writes Riccardo Cascioli in La nuova Bussola Quotidiana, a widely read Italian Catholic website.

While detractors are lining up against the pope, many welcome the encyclical as a teaching document that reframes the environmental debate — particularly humanity's response to climate change — within the context of morality, along with a call to global action. Considering the failure over the past two decades of world leaders to come to any international climate change agreement, reframing the debate could help: Intended not just for the church and theologians, but for world leaders and the general public, it hopes to tap into something that goes far deeper than carbon trading and limits on greenhouse gas emissions: a duty to God. While atheists may cringe at the thought, for non-believers that idea can simply translate into a moral duty. Simply replace the word "God" with "Earth," and everyone has a seat at the table.

Here are five reasons Pope Francis' encyclical on the environment matters.

1. It builds on the foundation laid down by his predecessors.

Francis' encyclical is important because it capitalizes on the environmental discourse established by the previous two pontiffs. Pope Benedict, who immediately preceded Francis, is known as the first environmental pope. In a 2011 address to a group of Italian students, the so-called Green Pope said, "Respect for the human being and respect for nature are one and the same."

Benedict put his money where his mouth was: Not only did he install solar panels on the Vatican and turn the Popemobile into a hybrid electric car, he authorized the Vatican bank to purchase carbon credits by funding a Hungarian forest, a move that made the Vatican the world's first carbon-neutral country, and also showed the church's support for the economic-based climate change mitigation mechanism that underlies the Kyoto Protocol.

Pope John Paul II, Benedict's predecessor, may not have been as hands-on in terms of improving the Vatican's energy efficiency, but he was keenly aware of the importance of protecting the environment. In 2002, he issued the "Common Declaration of Environmental Ethics," in which he expressed concern about "the negative consequences for humanity and for all creation resulting from the degradation of some basic natural resources such as water, air and land, brought about by an economic and technological progress which does not recognize and take into account its limits."

2. It shows that Africa has a high-level climate champion.

By making environmental issues a top line item for the world, Pope Francis is being a good representative for his flock: Not only is Africa the region where the church has seen its most explosive growth, it is the continent most vulnerable to the effects of climate change. (Since 1980, Europe’s Catholic population grew by a mere six percent, while the number of African Catholics grew by 238 percent.)

"When it comes to climate change Africa is in the eye of the storm," argues Coleen Vogel, a professor at the School of Animal, Plant and Environmental Sciences at University of the Witwatersrand, in Johannesburg, South Africa. And it's not just because of Africa's unusually high exposure to climate risks like droughts and flooding. Vogel, one of the authors of the Africa Chapter of the 4th Assessment Report of the U.N.'s Intergovernmental Panel on Climate Change (IPCC), points out that the continent "has low adaptive capacity making it particularly vulnerable and exposed because of high rates of poverty, financial and technological constraints as well as a heavy reliance on rain-fed agriculture."

Pope Francis has made clear moves to help support outreach efforts in Africa, such as naming, in January, two Africans — Archbishop Berhaneyesus Demerew Souraphiel of Ethiopia and Bishop Arlindo Gomes Furtado of Cape Verde — to the College of Cardinals. Notably, nine of the 15 new members are from the developing world, reflecting the worldview of the first pope to hail from the global south. “From a global perspective, this is very important," said Patrick Nicholson, a spokesman for Caritas Internationalis, the Vatican's charity arm. "What the pope is saying [to the church] is, go to the peripheries and try to help the most vulnerable communities."

"Consistent with the Catholic notion of the 'preferential option for the poor,' Pope Francis has repeatedly emphasized the vulnerability of the poor to environmental crises," notes Rabbi Lawrence Troster, founder of Shomrei Breishit: Rabbis and Cantors for the Earth, a multi-denominational network of rabbis and cantors advocating climate change action and environmental justice. "In line with the teachings of every major religion, [the encyclical] will urge leaders to protect from environment-related devastation those who have been 'excluded' from the world economic system."

3. It comes at a critical time for the world.

In his speech in March, Cardinal Turkson pointed out why the release of the document is timely:

The timing of the encyclical is significant: 2015 is a critical year for humanity. In July, nations will gather for the Third International Conference on Financing for Development in Addis Ababa. In September, the U.N. General Assembly should agree on a new set of sustainable development goals running until 2030. In December, the Climate Change Conference in Paris will receive the plans and commitments of each government to slow or reduce global warming. The coming 10 months are crucial, then, for decisions about international development, human flourishing and care for the common home we call planet Earth.

Jeff Nesbit, former director of legislative and public affairs at the National Science Foundation under the Bush and Obama administrations, argues that "climate change is rapidly becoming the moral issue of our time." He underscores the social dimension of the debate:

People of all ages, from all demographics and all corners of the planet, are beginning to recognize that significant changes are occurring in our ecosystem, and they’d like to see someone, anyone, do something about it. They’re beginning to challenge leaders to act boldly. They’re learning how to act as low-carbon consumers. They’re demanding an end to the fossil fuel age. They’re turning a distant threat into a moral cause that demands a much more immediate response from business and political leaders.

Nesbit believes that, because it is armed with the moral authority of a hugely popular pope, the encyclical "has the potential to catalyze a great deal of action across the world when it’s issued."

4. It helps reduce the rift between science and religion.

As part of the "encyclical tour" to help ensure that the document has a strong impact leading up to the Paris climate talks, the Vatican has aligned itself with the scientific and global development communities. In April, an event at the Vatican titled "Protect the Earth, Dignify Humanity: The Moral Dimensions of Climate Change and Sustainable Development" helped to establish the parameters of the dialogue for the coming months.

Organized by the Pontifical Academy of Sciences; the Pontifical Academy of Social Sciences; the Sustainable Development Solutions Network, a U.N. initiative; and Religions for Peace, an international multi-religious peace advocacy coalition, the event was opened by a speech from U.N. Secretary-General Ban Ki-moon, who pointed out that the major religions represent the third largest category of investors in the world. "I urge you to invest in the clean energy solutions that will benefit the poor and clear our air," he said. "Sustainable development requires sustainable energy for all. I also urge you to continue to reduce your footprint and educate your followers to reduce thoughtless consumption."

It makes sense that the pope is contributing to a scientific debate: Francis is a Jesuit, a Roman Catholic order of religious men known for its strong connection to the sciences. From discovering the orbital phases of Mercury and writing on non-Euclidean geometry to participating in the discovery of Peking Man and helping found the Indian Association for the Cultivation of Science, Jesuits boast an impressive scientific record compared to other Catholic orders. If any pope can help heal the rift between religion and science, it's this one. It was Francis, after all, who said that the Big Bang theory is not inconsistent with Creation, telling an assembly of the Pontifical Academy of Sciences last fall that believers should not view God as "a magician, with a magic wand."

By helping to bridge the gap between science and religion, the encyclical can help foster a more inclusive dialogue on a host of other scientific queries that may benefit from a theological dimension. There's a reason, after all, that the elusive Higgs boson, an elementary particle in the Standard Model of particle physics that is believed to be the source of all matter in the universe, is nicknamed the "God particle." The late John Dobson, an astronomer and Vedantic monk in the Ramakrishna Order, argued that physicists and priests were essentially seeking answers to the same questions, just in different ways.

5. It has a significant reach, even beyond Catholicism.

You don't have to be Catholic to get behind the basic idea of protecting the environment. And if you don't respect the office of the pope, you still must respect its reach: Francis is the spiritual leader of some 1.2 billion Roman Catholics across the world. In any case, the main points of the encyclical will likely be non-denominational. One of the main themes will be that "the Earth is a gift from God and reflects a divinely ordained beauty and order," posits Rabbi Troster. "This theme is integral to Christianity, Judaism and Islam, which share an understanding of God as a magnificently generous creator."

Troster also asserts that one of the likely directives in the declaration — that humans must act as the stewards and protectors of the Earth — is a view held by all the major religions. "Judaism, Christianity and Islam offer variations on this theme, rooted in Biblical creation accounts and from passages from the Qur'an," he writes. "Hinduism and Buddhism, with their traditional teachings on ahimsa (non-violence), consistently emphasize that it is our dharma (duty) to treat the natural world with respect. The moral imperative to protect the earth is strong across all faiths."

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"An essential document for Roman Catholics, the encyclical will also be influential for other Christians and people of all faiths and good will," says Troster. "When the encyclical makes headlines, diverse faith leaders globally will want to highlight their own traditions' eco-teachings. This is good, because over the past two decades, eco-theologians globally have articulated values deeply consistent with the themes that Pope Francis can be expected to share." It will be interesting to see the response he gets when he shares those themes in September during a papal address to a joint session of Congress, which is rife with climate deniers, several of whom would be president.

Spirit, courage and faith

In 2000, the Acton Institute, a religious-based libertarian/conservative public policy think tank, published an essay titled "A Biblical Perspective on Environmental Stewardship," co-authored by Thomas Sieger Derr, a professor of religion at Smith College, and P.J. Hill, then-professor of economics at Wheaton College, among others. "As history has repeatedly shown," the authors argue, "it is the creative spirit of the human person that permits wise stewardship, and institutions that encourage this spirit are more likely to also facilitate environmentally sound ends." Their premise raises a fair question: What institution encourages the most creative spirit? Congress? The U.N.? The church?

There are ways a spiritual leader like the pope can offer a fresh viewpoint on the climate issue, particularly when politicians, legislators and international negotiators have failed so miserably for so long. When a discussion turns to the topic of environment, for example, Francis is fond of saying, "God always forgives, man sometimes forgives, but nature never forgives.” It's a shrewd aphorism that presents the climate issue in a different light.

Perhaps it's the perfect time to give the mantle of climate change leadership to the first truly modern pope. "Francis’ upbeat, quotable approach and emphasis on charity over doctrine have quickly made him perhaps the most talked about and admired person on the planet," observed Shawn Tully, an editor-at-large at Fortune, which named the pope No. 1 on its World’s Greatest Leaders list last year. And really, who else do we have? President Obama? Ban Ki-moon? Al Gore? No one has the nearly the global reach and respect that Pope Francis does.

During a recent Q&A, Senator Elizabeth Warren (D-MA) said, "Too many of the people in Washington do not represent the folks who elected them." On certain issues, like protecting the Earth/creation, could society be better served by their spiritual leaders than their political leaders? It's certainly worth a try. In the end, addressing climate change through a combination of the two could be productive.

In his earliest days as pontiff, Francis recognized the centrality of environmental stewardship to the future of humanity. Just after his election, he said he chose the name Francis of Assisi because “for me, he is the man of poverty, the man of peace, the man who loves and protects creation. These days we do not have a very good relationship with creation, do we?”

No matter if you call it creation, Earth, the environment or the Big Blue Marble, by many measures, humanity hasn't been the best caretaker of a planet shared by 7.2 billion humans and many, many billions of other Earthlings who live and die by our decisions. And while Pope Francis' encyclical won't by itself limit the average global surface temperature increase to 2°C — which a majority of scientists agree will prevent the worst effects of climate change — it may have the power to be a spiritual salve that helps loosen the gridlock that has dogged international climate negotiators for the past 20 years.

Speaking at a January 15 press conference, Pope Francis said the last U.N. climate change conference, held in Lima, Peru, in December, “was nothing great. I was disappointed by the lack of courage; things came to a stop at a certain point. Let’s hope that in Paris the delegates will be more courageous.” More courage would certainly be good — and perhaps a little faith.

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