Justin Welby will be enthroned as Archbishop of Canterbury today, marking the official start of his public ministry.
He will be enthroned in two special seats in Canterbury Cathedral in a ceremony due to be attended by 2,000 guests including the Prince of Wales, David Cameron, and archbishops and bishops from around the world.
Representatives of other faiths will also be in attendance.
The ceremony gets underway at 3pm when the Archbishop will deliver the traditional three knocks to the cathedral door.
He will be asked by the Archbishop of York, Dr John Sentamu, to swear an oath of faithfulness to the statutes of the Church of England and an oath of faithfulness to the Queen, the Supreme Governor of the Church of England.
The oath will be sworn on the ancient Canterbury Gospels, brought to England by St Augustine in 597.
The Archbishop will first be installed on the diocesan throne as the Bishop of the see of Canterbury, the oldest diocese in the English church.
The second seat is the chair of St Augustine, signifying his position as Primate of all England, or 'first bishop' in the country.
From here, the Archbishop will read the Gospel and preach a sermon to the congregation.
The Archbishop spent the run-up to his enthronement on a prayer pilgrimage around south-eastern England, where thousands turned out to greet him.
Writing in the Canterbury Times today, the Archbishop said he was "extremely pleased and excited" about his new position at the helm of the Church of England and Anglican Communion.
He added that he was looking forward "immensely" to serving the people of Canterbury Diocese.
"Canterbury is also where the Archbishop can do his work as a priest and a bishop – work which remains absolutely vital," he said.
"Having this close connection to Canterbury and its people is something I am looking forward to enormously."