Thousands of people marched in Rome on Sunday to promote Pope Francis’ historic call for global action on climate change. A Vatican encyclical this month urged world leaders to pay their “grave social debt” to the poor and take swift action to save the planet from environmental ruin. A march participant said the cause of climate justice unites all faiths.

Daniel Blackman: “I think what it’s saying is that globally the moral and the spiritual concern has grown. And the fact that there are so many different faiths says that communities are willing to put aside their differences and their different faiths to come together on a common issue. So, whether it’s the pope through the encyclical or it’s the Muslim community or the Christian community or the Catholic community, we have all come together to address it, because it’s an issue that affects all of us as human beings.”

The Vatican is hosting a conference on climate change this week with activists and scientists from around the world.