Even by the standards of Church ritual, the confirmation of an Archbishop of Canterbury's election is an extraordinary event. Senior bishops will sit in St Paul's Cathedral as a court of law, using elaborate language and flowery titles to certify Justin Welby in his new post. The ceremony, little changed over centuries, was originally intended to prevent false claimants being appointed to what were lucrative posts as bishop. Bishop Welby's enthronement, amid colourful ritual and soaring music, is next month in Canterbury Cathedral, and the event has usually eclipsed this legal ceremony. However, Justin Welby requested that today's event be set in a full church service, including hymns and a sermon, to reflect the essentially religious nature of his new post. As the Archbishop of York, John Sentamu, reads and signs a "final proclamation", Bishop Welby will become archbishop, and spiritual leader of some 80 million Anglicans across the world.