Prince Charles? Coronation? I must have missed something. I know almost nothing about royal succession, but Charles should step aside and allow his son to become king when the time comes. He should never ascend to the throne.
Just forward planning. Plans are always underway at some level for these ceremonials even if they are not anticipated for a long time - but as the Queen is 88, it is considered quite reasonable to think it might happen in the relatively near future. They're not sentimental about this. "The Queen is dead. Long live the King" is a constitutional fact to be faced whenever it happens. And even if the Coronation isn't that of Prince Charles, there would be a Coronation.
But this change is not going to happen - the form of the Coronation, which is a Sacrament of the Church of England, and was a Sacrament of the Roman Catholic Church before it, has been more or less fixed without major change since 1307. It's a Christian service and it cannot incorporate readings from a non-Christian faith. Lord Harries is simply spouting off in the Lords.
I know almost nothing about royal succession, but Charles should step aside and allow his son to become king when the time comes. He should never ascend to the throne.
He can't completely avoid it. Constitutionally he becomes King the instant his mother dies and he has no power not to do so (Parliament can alter the succession - nobody in the Royal Family can do it.) He could abdicate in favour of his son before Coronation, but he would still be King from the moment of his mother's death until the Instrument of Abdication took effect.
And he won't do this for a number of reasons. Not unless he was physically too old, sick, or infirm to take the crown - which at the moment he certainly isn't - he's getting older but he's still perfectly healthy. The main reasons he won't do it though is that he has a duty to his country to take the crown. Whatever people may think of the idea of monarchy, he doesn't get a choice. It's a duty under his nation's constitutional law, and he has spent his entire life doing his duty under that law. This is not the life he would have chosen - but he's done what he's supposed to all the same. Secondly, and almost as importantly, he won't drop the responsibility onto William. He decided a long time ago that he wanted his sons to have closer to a normal life than he ever managed. Their duty means they can't have entirely normal lives, but they have managed it to a great extent and every day that Charles sits on the throne is one more day that William does not have to.
I'm lucky enough to know the Prince personally. He's a good, decent man, with very little resemblance to the caricature of him people get from the media. He's just a man - flawed like any other - nothing special in any way except an accident of birth, but he is dedicated to his country and to the Commonwealth and to doing his duty. His motto as Prince of Wales (which like so much in his life he didn't choose) is "Ich Dien" - 'I Serve' and he has taken it as a personal motto. When the Crown falls to him, he will do his duty, and I really see no reason for anyone to think he won't be a good King.