"Let's talk in language that is understood across the heartland about faith," said Buttigieg, an openly gay presidential candidate.
"You know, if you believe that God is watching as poison is being belched into the air of creation, and people are being harmed by it ‐ countries are at risk of vanishing in low-lying areas ‐ what do you suppose God thinks of that?" he asked rhetorically.
"I bet He thinks it's messed up," Buttigieg answered.
"And you don't have to be religious to see the moral dimensions of this, because frankly, every religious and non-religious moral tradition tell us that we have some responsibility of stewardship, some responsibility for taking care of what's around us," he continued.
"Not to mention taking care of our neighbor. Eventually it gets to the point where this is less and less about the planet as an abstract thing, and more and more about specific people suffering specific harm because of what we're doing right now," he added.
"At least one way of talking about this is that it's a kind of sin," Buttigieg concluded.
The South Bend, Indiana, mayor experienced a surge in polling early in the 2020 nomination race, but his support has since tumbled back to Earth. He is polling at 5 percent, tied for fourth place, in recent polling.