The Pope of the encyclical Laudato si’ and the “green” Patriarch are worried about the “tragic and lasting” consequences of human action on the environment. “The human and the natural environments are deteriorating together, and such deterioration of the planet weighs on the more vulnerable people. The impact of climate change impacts above all on the people who live in poor conditions in every corner of the globe. Our duty to use the assets of the Earth responsibly involves acknowledging and respecting every person and all living creatures. The call and the urgent challenge to take care of Creation are an invitation to all mankind to work for a sustainable, integral development”. Hence the pressing call to “all the men of good will to devote, on September 1^st, a moment of prayer for the environment”, in the attempt to “change the way we perceive the world in order to change the way we relate to the world. The purpose that we set out for ourselves – Francesco and Bartholomew conclude – is to be daring in embracing more simplicity and solidarity in our lifestyles.