When the royal family is staying at Sandringham, the crowds turn out in all weathers to greet them when they go to Sunday services at St Mary Magdalene’s Church, 400 yards from the big house on the Sandringham estate. The sixteenth-century church, with its richly decorated chancel and magnificent silver altar, has been the site of many significant christenings, including those of the future King George VI in 1896 and Lady Diana Spencer, whose parents lived on the Sandringham estate in 1961. The most recent one came in July 2015, when Princess Charlotte of Cambridge, their great-granddaughter, was christened there.

When they are in Scotland at Balmoral, the Queen and Prince Philip have the royal pew at Crathie Kirk, a small Church of Scotland parish church. The Princess Royal married her second husband, Timothy Laurence, at the church because she was divorced and, at the time, not permitted to marry in the Church of England.

Even when the royal family were at sea, on board the royal yacht Britannia in the days when overseas tours were a regular part of the royal calendar, there would always be a service held on a Sunday. Admiral Woodard, one-time commodore of Britannia, said that the Queen preferred not to travel with a chaplain on board because she did not like sermons. Instead, she would ask Admiral Woodard to take the service. He added: ‘But she knows her Bible. I’d go to the Queen with suggestions about readings and hymns and she would quote the Bible without bothering to look it up. The prescribed reading might start at, say, verse nine, but the Queen would say: “No, let’s start at verse seven, otherwise it won’t have the proper sense.” ’

Time and again in her Christmas Day speeches to the nation and the Commonwealth, the Queen has stressed the importance of her religious beliefs. In the millennial year address, she said: ‘To many of us our beliefs are of fundamental importance. For me the teachings of Christ and my own personal accountability before God provide a framework in which I try to lead my life. I, like so many of you, have drawn great comfort in difficult times from Christ’s words and example.’

Again, as part of the television broadcast she made in 2015, she said: ‘For me, the life of Jesus Christ, the Prince of Peace, whose birth we celebrate today, is an inspiration and an anchor in my life. A role model of reconciliation and forgiveness, he stretched out his hands in love, acceptance and healing. Christ’s example has taught me to seek to respect and value all people of whatever faith or none.’