Corbyn had been due Thursday to be sworn in to the Privy Council — a body of senior statesmen and women who advise the monarch on matters of state — but turned it down, citing prior engagements. Corbyn has been a republican all his life and has strong views on the Queen's role in the state.
How strong is a democracy or reason when 21st century elites queue to kneel before a monarch anointed by god to rule over us #PrivyCouncil— Harry Leslie Smith (@Harryslaststand) October 8, 2015
As Labour leader, he could — albeit a long-shot — win the next election and become Prime Minister. As such, he would have to seek permission of the Queen to form an administration and then lead "Her Majesty's Government" — both of which are anathema to the staunch republican.
The role of the Privy Council dates back to Norman times when English kings and queens were advised by a royal court consisting of the great and good among the rich magnates, the clergy and senior officials.
Corbyn would have been asked to swear the Privy Council oath which begins: "You do swear by Almighty God to be a true and faithful Servant unto the Queen's Majesty, as one of Her Majesty's Privy Council. You will not know or understand of any manner of thing to be attempted, done, or spoken against Her Majesty's Person, Honour, Crown, or Dignity Royal, but you will lett and withstand the same to the uttermost of your Power…"
He drew criticism within a week of becoming Labour leader by refusing to sing the national anthem at the Battle of Britain memorial service at St Paul's Cathedral, his first ceremonial event since being elected Labour leader. Embarrassed party officials later told the media he would be singing the anthem at the next major occasion.
As a life-long pacifist, a leading figure in the Campaign for Nuclear Disarmament and the Stop the War Coalition, he would — if he became prime minister — have to be responsible for defense decisions over "Her Majesty's Armed Forces".
At his first State Opening of Parliament, he would have to sit and watch the spectacular royal procession and listen to the Queen's Speech in which she sets out what "my government" is planning to do.
In 1998, he told the Beaver County Times that:
"It's absolutely ridiculous, this 18th-century performance, the horses and the knights and everybody else turning up for The Queen to read a speech she's never even read before, let alone written."
He joined the late veteran left-wing Labour lawmaker Tony Benn in calling for the transformation of Britain into a "democratic, federal and secular Commonwealth of Britain", with an elected president, and the abolition of the House of Lords as it currently exists.
As a Privy Counselor, Corbyn would be referred to by his colleagues in parliament as "The Right Honorable Member" – a fact that has recently been cause for some amusement in Westminster circles with regard to another Privy Counselor, Prime Minister David Cameron, who was alleged to have put a "private part of his anatomy" into a dead pig’s head as part of a posh dining club initiation ritual when he was a student – a claim which the right honorable member's owner denies.
With the Labour Party already split over Corbyn's leadership and 90 percent of his parliamentary colleagues radically opposed to his views on defense, foreign policy, the monarchy and much more, the failure to join in the ancient ritual will be seen as further evidence of disunity within the party.
The political importance of Corbyn's refusal to take part in the swearing in ceremony to become a member of the Privy Council — alongside elder statesmen, leading politicians, former prime ministers and a pool of the great and the good advising Queen Elizabeth — is that many will see this as another snub to the monarch, which may render him unpopular with a significant number of voters and the Labour Party therefore unelectable.