The apostolic letter given motu proprio by which Benedict XVI announced a Year of Faith, to run from 11 October 2012 — the fiftieth anniversary of the opening of the Second Vatican Council and the twentieth of the publication of the Catechism — to the Solemnity of Christ the King in 2013. Taking its title from the Acts of the Apostles' 'door of faith', it calls for a rediscovery of the journey of faith, a renewed reading of the Council's documents and of the Catechism, a profession of the Creed, and a faith that works through charity, so that the new evangelisation may be rooted in conversion.