On Care for Our Common Home by Sean McDonagh Orbis Books, £12.99 Papal encyclicals always guide the Church but only a very few of them directly change the world. Laudato Si’ has already had that global impact. None of us who participated in the successful climate negotiations in Paris could mistake the profound effect of Pope Francis’s words. He turned climate change from a problem in and of itself into a potent symptom of the central concern of human existence – the way people treat each other and the rest of Creation. In this commentary on Laudato Si’, Irish priest Fr Sean McDonagh puts the encyclical into its historic context and then leads us through its uncompromising challenges. Laudato Si’ re-read in the light of his perceptive analysis is a source of even greater wonderment and inspiration. In accepting the scientific truth that human actions are changing the climate, the Pope was concerned not just with its effects on mankind but also upon the animal kingdom, the flora and fauna, the rivers and the oceans. In true Franciscan spirit, he characterised climate change as an assault on Creation. But he also recognised that this was an assault upon the poor. The encyclical adopts a holistic position far more comprehensive than most current political stances. It is not long since poverty campaigners were at loggerheads with environmentalists. Today there is real mutual recognition of their common goals. Climate change, biological degradation, the destruction of the oceans, are together the most powerful creators of poverty. Pope Francis took it one huge step further. He insisted that the teaching of the Church calls us to care for others, particularly the poor and dispossessed, as an integral part of our duty to care for all creation. These are not separate duties; there is no menu of choices. This is what Christ calls us to do. We can’t love our neighbour and desecrate the environment upon which we all depend. Fr McDonagh has a long history of feisty intervention in environmental debate but this introduction is balanced and considered. Only very occasionally do his prejudices about private ownership peep through, but never enough to irritate or distort. It is altogether a very valuable companion to the most important encyclical of modern times. Lord Deben is chairman of CCC, the UK’s independent Committee on Climate Change