The Queen did not want a "boring" funeral service, with a former archbishop saying tomorrow will be uplifting.
Former York archbishop of York Lord Sentamu said Shakespeare and angelic voices singing at their best will be among the focal points of the poignant event.
The Crossbench peer told the BBC's Sunday With Laura Kuenssberg programme the funeral would be the peak of the English language with joyous choral singing.
He said: "So what you're going to expect is the best of funeral services, the prayer book service, the words which were an inspiration to Shakespeare.
"So you're going to hear this wonderful English at its best, also you're going to hear angelic voices of the choir of the Abbey plus the Chapels Royal, you really hear voices that are singing to the glory of God.
Crowds will not be bored but will be lifted by the landmark day which will be an occasion which will warm people's hearts.
He said: "The Queen does not and did not want what you call long, boring services, you're not going to find boredom, but you're going to be lifted to glory as you hear the service."
"The hearts and people's cockles will be warmed and at the same time, there will be a moment of saying this is a funeral service that is glorious in its setting."
Military leaders, meanwhile, have signalled the importance of the day for the armed forces.
Admiral Sir Tony Radakin said soldiers taking part view it as their "last duty" to her.
The Chief of the Defence Staff told the BBC : "For all of us, this is our last duty for Her Majesty the Queen and it's our first prominent duty for His Majesty King Charles, and we're representing the nation, we're representing our mothers, our grandmothers, our fathers, our friends, and everybody's very, very aware of that."
He was questioned about the vigil at the Queen's lying in state in Westminster Hall and said it was an honour to take part.
Admiral Rankin added "Well, it's a huge honour and privilege, it's the first time that the chiefs have done that.
"And I think there's a mixture of emotions, my view of the hall is this sense of respectfulness that the public coming through and paying their own private respects and our contribution to that, and at the heart of it is remembering that there is a grieving family."
But he also added that it was important detail and precision about sombre state occasion.
He added: "There's a solemnity and precision about what you're doing and there's a need to concentrate to stay still for 20 minutes but then it's also an act of reflection.
"And my personal piece was just reflecting on Her Majesty the Queen, several audiences that I been privileged to have with her, and this sense of gratitude, gratitude for what she provided to our nation, and tried to express that with the love and affection that you're seeing throughout the country."
