This book, consisting of nine essays on the causes, on the figures involved and on the consequences of the decree, sheds light on various philosophical, theological, political and cultural aspects of the discussions that arose around the 'temerity' of Copernicanism and that eventually led to its prohibition by the Church. These chapters form a mosaic whose pieces contribute to completing the picture outlined by other studies, while also adding new meaning to the overall scenario.This volume deals with the anti-Copernican decree issued by the Holy Office of the Catholic Church on 5 March 1616, and is being published on the occasion of the fourth centenary of the promulgation of this ban. Adopting a different perspective from the mainstream of Galilean studies, this book aims to bring the 'entangled matter' of the anti-Copernican decree, which has hitherto been overshadowed by the 1633 trial of Galileo, into the foreground and give it the attention it deserves. Composed of nine essays dedicated to the causes, the promotion and the aftermath of the decree, the book sheds light on various philosophical, theological, political and cultural aspects of the discussions that arose around the 'temerity' of Copernicanism and, in the end, its prohibition by the Church. The chapters form a mosaic whose pieces not only contribute to the completion of the picture outlined by other studies, both by building on their conclusions and engaging in a fruitful dialogue with them, but which also give new meaning to the whole scenario.