As a chorister at King’s College, Cambridge, a young Bob Chilcott quickly became familiar with some of the greatest Requiem settings in the choral repertoire – notably those by Fauré and Duruflé, and Benjamin Britten’s War Requiem. So when it came to writing his own setting, these works were a major inspiration.

“I used to sing the Fauré and Duruflé settings every year when I was a boy, so they’ve become ingrained in my mind,” he tells me. “I sang Pie Jesu on the 1968 recording of the Fauré Requiem, so it means something particular to me and my family, because just when that recording came out my dad died, so it’s ingrained in our family story.”

Bob’s Requiem has been co-commissioned by the Oxford Bach Choir, Music at Oxford and the Preston Hollow Sanctuary Choir in Dallas, Texas. The world premiere by the Oxford Bach Choir and the Royal Philharmonic Orchestra, conducted by Nicholas Cleobury, will be at the Sheldonian on March 13, in tandem with Beethoven’s Mass in C. But audiences familiar with the Requiem texts will be in for a surprise – there’s no Dies Irae or Libera Me in this version, and Bob has inserted English text.

“In the great Requiems there are dramatic settings of Dies Irae, but I have a difficulty with the idea of this wrathful, vengeful God,” he explains. “So it dictated to me a gentle work. Fundamentally, it’s a traditional setting of the Latin Mass, but I’ve included a setting of the sentence ‘Thou knowest, Lord, the secrets of our hearts’, from the funeral sentences in the Book of Common Prayer.

“I’ve always loved melody, and there’s a lot of melody in it. The piece is about 35 minutes long, and I’ve tried to establish an atmosphere and to take the listener and performers into that atmosphere. I find writing in Latin has a different resonance, in that your point of is reference is steeped in cultural memory. So the import of the words becomes based on all the settings that I’ve remembered. In a sense it’s made the piece more meditative, because that’s how I remember those words.

“For me, the challenge will be whether it stands up as a concert piece and as a liturgical piece. Some liturgical pieces, when they’re performed in the concert hall, are harder to listen to in that context. So I hope I’ve managed that!”

Another unusual aspect of the work is that there are only two soloists, a soprano and a tenor, instead of the standard four. “The piece is quite gentle but it’s also got a lot of rich writing over a lot of pedals, and I wanted the high voices to counter that,” he says. “The soprano part sings above the choir quite a lot, which I like. I like the setting of a soloist with the choir, and I think with the higher voices it’s easier to do that. I didn’t want that quartet of solos sound – it didn’t seem appropriate to me.”

The premiere will be preceded by a performance by pupils of St Gregory the Great School and Cherwell School, who are taking part in workshops led by animateur James Redwood, with members of the choir and the Royal Philharmonic Orchestra, to create a piece inspired by Bob’s Requiem.

“I’m looking forward to it enormously,” says Martin Peters, the OBC’s Artistic Director. “The exciting thing about these projects is that they are fresh and they evolve, so from the first session we’ll see what ideas come forward and how we flesh those out. Because that’s what they’re all about, really – creativity, spontaneity and picking up on ideas, developing them, and using the material that the students offer.

“It’ll be hard work as we haven’t got a lot of time to put things together, but they usually come up with something that’s really refreshing and spontaneous. Hopefully, by raising the aspirations of the students, and enabling them to work closely with professional musicians, it’ll give them a good opportunity to do something that’s completely different but that complements their work in school.”

Meanwhile, Bob is looking forward with some trepidation to hearing his work performed for the first time. “I am excited, but I get terribly nervous,” he admits. “It’s a two-edged sword, because you really look forward to it, but at the same time, there’s a part of me that would rather not be there. “But I’ve known Nick Cleobury a long time, he’s a very fine musician, and his energy his helped me to bring this piece about, so I’m very grateful to him.”

The performance is on Saturday, March 13. For tickets tel: 0870 7500659 or visit www.musicatoxford.com