Pope Francis, the leader of the Catholic church, died on Monday (April 21, 2025) after months-long battle with pneumonia. Pope Francis was loved widely for a number of reasons, and one of them was his push to address the climate crisis.

Two of his key messages were Lautado Si and Laudate Deum.

Lautado Si, on care for our common home

In May 2015, Pope Francis wrote an encyclical to bishops of the Roman Catholic Church, highlighting the ecological crisis that the earth is facing.

This was, however, not the first instance when a Pope wrote a letter highlighting this. In his encyclical, Pope Francis referred to similar previous appeals – like the one by Pope Paul VI in 1971 where he said that the ecological crisis was a “a tragic consequence” of unchecked human activity: “Due to an ill-considered exploitation of nature, humanity runs the risk of destroying it and becoming in turn a victim of this degradation.” In his first encyclical, Pope Paul VI warned that human beings frequently seem “to see no other meaning in their natural environment than what serves for immediate use and consumption,” and later called for a “global ecological conversion.”

Pope Francis chose his papal name after St. Francis of Assisi, who he referred to in his encyclical as the “patron saint of all who study and work in the area of ecology, and he is also much loved by non-Christians.”

Pope’s appeal

Pope Francis appealed to the people to protect “our common home” while seeking “sustainable and integral development.” He suggested a dialogue about the future of the earth to address environmental challenges.

“Many efforts to seek concrete solutions to the environmental crisis have proved ineffective, not only because of powerful opposition but also because of a more general lack of interest. Obstructionist attitudes, even on the part of believers, can range from denial of the problem to indifference, nonchalant resignation or blind confidence in technical solutions,” he wrote in his encyclical.

He also stressed on the urgency of environmental challenges, including how pollution causes health hazards, “throwaway culture” that generates excessive amounts of waste, water wastage, biodiversity loss, and more.

He called climate “a common good”, and said that humans need to change their lifestyle, production, and consumption choices to prevent global warming. He warned about the effects of unabated use of fossil fuels, and said, “If present trends continue, this century may well witness extraordinary climate change and an unprecedented destruction of ecosystems, with serious consequences for all of us.”

Pope Francis not only talked about the ecological aspects of climate change, but the social ones too. He said that inequitable distribution and consumption of energy and other services, social breakdown, increased violence, etc, indicate a social decline.

“A true ‘ecological debt’ exists, particularly between the global north and south, connected to commercial imbalances with effects on the environment, and the disproportionate use of natural resources by certain countries over long periods of time,” he said.

He also called out international political responses to the climate crisis and global warming, and said that they have been “weak.”

“The failure of global summits on the environment make it plain that our politics are subject to technology and finance. There are too many special interests, and economic interests easily end up trumping the common good and manipulating information so that their own plans will not be affected,” Pope Francis said.

Laudate Deum (2023)

Eight years after he wrote the Laudato Si encyclical, Pope Francis followed up his appeal to safeguard the earth from the climate crisis with Laudate Deum, an apostolic exhortation, or a message to the people. He said that our response to the global climate crisis has not been adequate, and the world may be nearing a “breaking point.”

In his message, Pope Francis said that signs of climate change are “increasingly evident,” with unusual heat, frequent extreme weather events, and more. He refuted claims made by some people that the earth has always had periods of warming and cooling, and said that we are currently witnessing unusually accelerated warming.

He alleviated the poor from the blame of the climate crisis, and said that “a low, richer percentage of the planet contaminates more than the poorest 50% of the total world population, and that per capita emissions of the richer countries are much greater than those of the poorer ones.”