In this book Bruno Latour calls upon Christians to join the struggle to avert a climate catastrophe. First and foremost, Christians need to overcome their lack of interest in 'earthly things' and pay attention to the Earth at a time when it is being neglected. He also urges Christians to renew their understanding of their faith in the context of the new image of the world that has emerged from Earth system science - that of a world in which the myriad of beings that inhabit the world are interdependent and living in close proximity on a slender, fragile membrane on the surface of the planet. This new image of the world cannot fail to have an impact on the sciences, on politics and on religion, just as, in earlier centuries, the cosmology of Copernicus and Galileo upset the old order. Latour sees the ecological crisis, and the cosmological mutation that it entails, as an opportunity to convey anew, to the largest possible audience, the tradition of Christianity as it has never been appreciated before, by bringing to bear the lessons of eschatology on the great crisis that looms before us all.