Pope John Paul II, Pope Benedict XVI and Pope Francis accepted the reality of human-caused climate change and recognized it as a moral issue. The following are some of their most relevant quotes.

Saint John Paul II:

  • Message for the World day of Peace, “Peace with God the Creator, Peace with all of creation (1990):
    “In our day, there is a growing awareness that world peace is threatened not only by the arms race, regional conflicts and continued injustices among peoples and nations, but also by a lack of due respect for nature, by the plundering of natural resources and by a progressive decline in the quality of life. (…) Faced with the widespread destruction of the environment, people everywhere are coming to understand that we cannot continue to use the goods of the earth as we have in the past. (…) The gradual depletion of the ozone layer and the related “greenhouse effect”has now reached crisis proportions as a consequence of industrial growth, massive urban concentrations and vastly increased energy needs. Industrial waste, the burning of fossil fuels, unrestricted deforestation, the use of certain types of herbicides, coolants and propellants: all of these are known to harm the atmosphere and environment. The resulting meteorological and atmospheric changes range from damage to health to the possible future submersion of low-lying lands. (…) The ecological crisis reveals the urgent moral need for a new solidarity, especially in relations between the developing nations and those that are highly industrialized. (…) When the ecological crisis is set within the broader context of the search for peace within society, we can understand better the importance of giving attention to what the earth and its atmosphere are telling us: namely, that there is an order in the universe which must be respected, and that the human person, endowed with the capability of choosing freely, has a grave responsibility to preserve this order for the well-being of future generations. I wish to repeat that the ecological crisis is a moral issue. (…) At the conclusion of this Message, I should like to address directly my brothers and sisters in the Catholic Church, in order to remind them of their serious obligation to care for all of creation.”
  • Message for the World day of Peace, “Respect for human rights: the secret of true peace (1999):
    “The promotion of human dignity is linked to the right to a healthy environment, since this right highlights the dynamics of the relationship between the individual and society. A body of international, regional and national norms on the environment is gradually giving juridic form to this right. But juridic measures by themselves are not sufficient. The danger of serious damage to land and sea, and to the climate, flora and fauna, calls for a profound change in modern civilization’s typical consumer lifestyle, particularly in the richer countries. (…) The world’s present and future depend on the safeguarding of creation, because of the endless interdependence between human beings and their environment. Placing human well-being at the centre of concern for the environment is actually the surest way of safeguarding creation; this in fact stimulates the responsibility of the individual with regard to natural resources and their judicious use.”
  • General Audience, 17 January 2001:
    “Unfortunately, if we scan the regions of our planet, we immediately see that humanity has disappointed God’s expectations. Man, especially in our time, has without hesitation devastated wooded plains and valleys, polluted waters, disfigured the earth’s habitat, made the air unbreathable, disturbed the hydrogeological and atmospheric systems, turned luxuriant areas into deserts and undertaken forms of unrestrained industrialization, degrading that “flowerbed” – to use an image from Dante Alighieri (Paradiso, XXII, 151) – which is the earth, our dwelling-place. We must therefore encourage and support the “ecological conversion” which in recent decades has made humanity more sensitive to the catastrophe to which it has been heading. Man is no longer the Creator’s “steward”, but an autonomous despot, who is finally beginning to understand that he must stop at the edge of the abyss.
  • Further environmental teachings of St John Paul II can be found here.

Pope Benedict XVI:

  • World Day of Peace Message, “If You Want to Cultivate Peace, Protect Creation” (2010):
    “Respect for creation is of immense consequence, not least because “creation is the beginning and the foundation of all God’s works”, and its preservation has now become essential for the pacific coexistence of mankind. (…) Can we remain indifferent before the problems associated with such realities as climate change, desertification, the deterioration and loss of productivity in vast agricultural areas, the pollution of rivers and aquifers, the loss of biodiversity, the increase of natural catastrophes and the deforestation of equatorial and tropical regions? Can we disregard the growing phenomenon of “environmental refugees”, people who are forced by the degradation of their natural habitat to forsake it – and often their possessions as well – in order to face the dangers and uncertainties of forced displacement? (…) A greater sense of intergenerational solidarity is urgently needed. Future generations cannot be saddled with the cost of our use of common environmental resources. (…) The Church has a responsibility towards creation, and she considers it her duty to exercise that responsibility in public life, in order to protect earth, water and air as gifts of God the Creator meant for everyone, and above all to save mankind from the danger of self-destruction.”
  • Papal Encyclical Caritas in Veritate (2009):
    “The environment is God’s gift to everyone, and in our use of it we have a responsibility towards the poor, towards future generations and towards humanity as a whole. (…) There is a pressing moral need for renewed solidarity, especially in relationships between developing countries and those that are highly industrialized. The technologically advanced societies can and must lower their domestic energy consumption, either through an evolution in manufacturing methods or through greater ecological sensitivity among their citizens. It should be added that at present it is possible to achieve improved energy efficiency while at the same time encouraging research into alternative forms of energy. (…) It is likewise incumbent upon the competent authorities to make every effort to ensure that the economic and social costs of using up shared environmental resources are recognized with transparency and fully borne by those who incur them, not by other peoples or future generations: the protection of the environment, of resources and of the climate obliges all international leaders to act jointly and to show a readiness to work in good faith, respecting the law and promoting solidarity with the weakest regions of the planet. (…) The way humanity treats the environment influences the way it treats itself, and vice versa. This invites contemporary society to a serious review of its life-style, which, in many parts of the world, is prone to hedonism and consumerism, regardless of their harmful consequences. (…) The Church has a responsibility towards creation and she must assert this responsibility in the public sphere. In so doing, she must defend not only earth, water and air as gifts of creation that belong to everyone. She must above all protect mankind from self-destruction. There is need for what might be called a human ecology, correctly understood. The deterioration of nature is in fact closely connected to the culture that shapes human coexistence: when “human ecology” is respected within society, environmental ecology also benefits.”
  • Light of the World: The Pope, The Church and the Signs Of The Times, pp. 42-9 (2010):
    “In view of the threatening [climate] catastrophe, there is the recognition everywhere that we must make moral decisions. There is also a more or less a pronounced awareness of a global responsibility for it; that ethics must no longer refer merely to one’s own group or one’s own nation, but rather must keep the earth and all people in view. The question is therefore: How can the great moral will, which everybody affirms and everyone invokes, become a personal decision? For unless that happens, politics remains impotent. Who, therefore can ensure that this general awareness also penetrates the personal sphere? This can be done only by an authority that touches the conscience, that is close to the individual and does not merely call for eye-catching events. In that respect this is a challenge for the Church. She not only has a major responsibility; she is, I would say, often the only hope. For she is so close to peoples consciences that she can move them to particular acts of self-denial and can inculcate basic attitudes in souls.”
  • Address to the Members of the Diplomatic Corps Accredited to the Holy See (2012):
    “We cannot disregard the grave natural calamities which in 2011 affected various regions of South-East Asia, or ecological disasters like that of the Fukushima nuclear plant in Japan. Environmental protection and the connection between fighting poverty and fighting climate change are important areas for the promotion of integral human development.”
  • Angelus- November 27, 2011:
    “The Convention of the United Nations Organization on climate change and the Kyoto Protocol will begin tomorrow in Durban, South Africa. I hope that all the members of the international community will agree on a responsible, credible and supportive response to this worrying and complex phenomenon, taking into account the needs of the poorest populations and of the generations to come.”
  • Address to students, November 2011:
    If, in fact, man forgets in his work that he is a collaborator of God, he can do violence to creation and cause untold damage that always has negative consequences, also on human beings, as we have unfortunately seen on various occasions. Today, more than ever, it appears clear to us that respect for the environment cannot fail to recognize the value and inviolability of the human person in every phase of life and in every condition. Respect for the human being and respect for nature are one and the same, but they will both be able to develop and to reach their full dimension if we respect the Creator and his creature in the human being and in nature.”
  • Address to the Members of the Diplomatic Corps for the Traditional Exchange of New Year’s Greetings (2010)
    “The denial of God distorts the freedom of the human person, yet it also devastates creation. It follows that the protection of creation is not principally a response to an aesthetic need, but much more to a moral need, in as much as nature expresses a plan of love and truth which is prior to us and which comes from God. For this reason I share the growing concern caused by economic and political resistance to combatting the degradation of the environment. This problem was evident even recently, during the XV Session of the Conference of the States Parties to the United Nations Framework Convention on Climate Change held in Copenhagen from 7 to 18 December last. I trust that in the course of this year, first in Bonn and later in Mexico City, it will be possible to reach an agreement for effectively dealing with this question. The issue is all the more important in that the very future of some nations is at stake, particularly some island states.”
  • Message to Summit on Climate Change (2009):
    “The Earth is indeed a precious gift of the Creator who, in designing its intrinsic order, has given us guidelines that assist us as stewards of his creation. Precisely from within this framework, the Church considers that matters concerning the environment and its protection are intimately linked with integral human development. (…) How important it is then, that the international community and individual governments send the right signals to their citizens and succeed in countering harmful ways of treating the environment! The economic and social costs of using up shared resources must be recognized with transparency and borne by those who incur them, and not by other peoples or future generations. The protection of the environment, and the safeguarding of resources and of the climate, oblige al leaders to act jointly, respecting the law and promoting solidarity with the weakest regions of the world.”
  • Letter of His Holiness Benedict XVI to the Ecumenical Patriarch of Constantinople on the Occasion of the Seventh Symposium of the Religion, Science and the Environment Movement:
    ”Preservation of the environment, promotion of sustainable development and particular attention to climate change are matters of grave concern for the entire human family. No nation or business sector can ignore the ethical implications present in all economic and social development. With increasing clarity scientific research demonstrates that the impact of human actions in any one place or region can have worldwide effects. The consequences of disregard for the environment cannot be limited to an immediate area or populus because they always harm human coexistence, and thus betray human dignity and violate the rights of citizens who desire to live in a safe environment.”

Pope Francis:

  • Speech at Santo Tomas University, Manila (2015):
    “A second key area where you are called to make a contribution is in showing concern for the environment. This is not only because this country, more than many others, is likely to be seriously affected by climate change. You are called to care for creation not only as responsible citizens, but also as followers of Christ!”
  • Address to the Members of the Diplomatic Corps Accredited to the Holy See (2015):
    “The drafting of a new Climate Change Agreement … is urgently needed.”
  • Address to Popular Movements (2014):
    “An economic system centered on the god of money also needs to plunder nature, to plunder nature to sustain the frenetic rhythm of consumption that is inherent to it. Climate change, the loss of bio-diversity, deforestation are already showing their devastating effects in the great cataclysms we witness, and you are the ones who suffer most, the humble, those who live near coasts in precarious dwellings or who are so vulnerable economically that, in face of a natural disaster, lose everything.”
  • Message to UN Convention on Climate Change (2014):
    “The effective struggle against global warming will only be possible with a responsible collective answer, that goes beyond particular interests and behavior and is developed free of political and economic pressures … On climate change, there is a clear, definitive and ineluctable ethical imperative to act … The establishment of an international climate change treaty is a grave ethical and moral responsibility.”
  • Audience (2014):
    Creation is not a property, which we can rule over at will; or, even less, is the property of only a few: Creation is a gift, it is a wonderful gift that God has given us, so that we care for it and we use it for the benefit of all, always with great respect and gratitude.”
  • Statement to the Diplomatic Corps (2014):
    “I wish to mention another threat to peace, which arises from the greedy exploitation of environmental resources. Even if ‘nature is at our disposition’, all too often we do not ‘respect it or consider it a gracious gift which we must care for and set at the service of our brothers and sisters, including future generations’. Here too what is crucial is responsibility on the part of all in pursuing, in a spirit of fraternity, policies respectful of this earth which is our common home. I recall a popular saying: ‘God always forgives, we sometimes forgive, but when nature – creation – is mistreated, she never forgives!’. We have also witnessed the devastating effects of several recent natural disasters. In particular, I would mention once more the numerous victims and the great devastation caused in the Philippines and other countries of South-East Asia as a result of typhoon Haiyan.”
  • Message For The Celebration Of The World Day Of Peace 2014 (2014):
    “The human family has received from the Creator a common gift: nature … Nature, in a word, is at our disposition and we are called to exercise a responsible stewardship over it. Yet so often we are driven by greed and by the arrogance of dominion, possession, manipulation and exploitation; we do not preserve nature; nor do we respect it or consider it a gracious gift which we must care for and set at the service of our brothers and sisters, including future generations.”
  • Apostolic Exhortation The Joy of the Gospel, n. 216 (2013):
    “Small yet strong in the love of God, like Saint Francis of Assisi, all of us, as Christians, are called to watch over and protect the fragile world in which we live, and all its peoples.”
  • Homily at the Solemnity of Saint Joseph (2013):
    “Let us protect Christ in our lives, so that we can protect others, so that we can protect creation! The vocation of being a “protector”, however, is not just something involving us Christians alone; it also has a prior dimension which is simply human, involving everyone. It means protecting all creation, the beauty of the created world, as the Book of Genesis tells us and as Saint Francis of Assisi showed us [. . .] In the end, everything has been entrusted to our protection, and all of us are responsible for it. Be protectors of God’s gifts! Whenever human beings fail to live up to this responsibility, whenever we fail to care for creation and for our brothers and sisters, the way is opened to destruction and hearts are hardened … Please, I would like to ask all those who have positions of responsibility in economic, political and social life, and all men and women of goodwill: let us be “protectors” of creation, protectors of God’s plan inscribed in nature, protectors of one another and of the environment. Let us not allow omens of destruction and death to accompany the advance of this world! … To protect creation, to protect every man and every woman, to look upon them with tenderness and love, is to open up a horizon of hope; it is to let a shaft of light break through the heavy clouds; it is to bring the warmth of hope! For believers, for us Christians, like Abraham, like Saint Joseph, the hope that we bring is set against the horizon of God, which has opened up before us in Christ. It is a hope built on the rock which is God.”