Mash up Eric Idle, “Life of Brian,” an orchestra, a full chorus, a handful of formidable Broadway names and a classically structured oratorio, and you’ve got “Not the Messiah (He’s a Very Naughty Boy).” Idle and composer John Du Prez’s follow-up to “Spamalot,” a send-up of Handel’s “Messiah” that’s also a stage adaptation of Monty Python’s 1979 comedy “Life of Brian,” premiered in 2007 at the Luminato Festival but is only now getting its Gotham premiere (at Carnegie Hall Dec. 15-16) from the Collegiate Chorale with the Orchestra of St. Luke’s. Along with Idle, soloists including notable Broadway types Victoria Clark (a Tony winner for “The Light in the Piazza”), Marc Kudisch and Lauren Worsham (“A Gentleman’s Guide to Love and Murder”). Also there are bagpipes.

How’d this upcoming New York run for the show come about?

St. Luke’s was the first American orchestra to do it, after we premiered it in Toronto. They were familiar with it. And Ted Sperling, who’s just become the artistic director of the Collegiate Chorale, directed me in “The Pirates of Penzance” in Central Park last year.

Sperling corralled a strong Broadway crew for the upcoming performances.

Oh my God, but they sing! I don’t think this piece has ever been sung so well. I’m not really a singer myself. I call myself “baritone-ish.”

You’ve got one opera performer as well, William Ferguson. What’s the difference between opera performers and Broadway performers?

Opera people are usually frightened of words, I find. I was nervous about having to sing, but I find that a lot of opera singers are terrified of having to speak.

So your show “Spamalot” had just become a Tony-winning Broadway hit, and you decided to adapt another of your well-known films… into an oratorio?

I don’t think you could ever put “Life of Brian” on stage, not even in New York. People would go nuts. They’d be there protesting every night. And my cousin is the conductor of the Toronto Symphony, and he was always on at me to do something. We thought, if Handel retells the life of Jesus in “The Messiah,” then why don’t we tell the story of Brian in the same way. And the oratorio is such a lovely form. Nobody ever does a comic oratorio. I do think some people are rather frightened, because they don’t know what the show is. The word ‘oratorio’ scares them and they don’t realize it’s funny. But it’s exactly what the show is, an oratorio like “The Messiah.” But with a bit more doo-wop.

Do you enjoy performing at Carnegie Hall?

I’ve performed at Carnegie two or three times. The first time was in 2000, when I was touring in “Eric Idle Exploits Monty Python,” and I was in full drag as Dolly Taylor singing “Sit on My Face.” I would have such a thrill getting dressed in the Brahms dressing room, adjusting my panty hose.

What’s your next stage project?

I’m working on some kind of weird show now. I’m not sure what it will be yet. I don’t know whether we’ll be doing it in a Broadway theater or in slightly larger halls. Not as large as the O2 in London, but bigger than a Broadway theater. I always write things first and see if it works.

Any chance we here in New York could see “Monty Python Live (Mostly),” the reunion show that played 10 performances at the O2 in the London over the summer?

No, I think that was it. We don’t want to turn into a touring group, going round the world and suddenly you’re the Eagles. It was great fun and very moving, but it was also very nice to say hello and goodbye.

You actually don’t perform live all that much. You ready for Monday night?

I’ve been training for it. I’ve been climbing the Hollywood Hills.

Do you enjoy being in New York?

I miss New York tremendously. We had “Spamalot” on here for five years. In fact, I’d booked lunch with Mike Nichols [who directed “Spamalot”] on Monday, who I miss terribly. Working on “Spamalot” was one of the best times of my life. It was one of those rare times in show business when everything goes right. That’s one reason why I like to move the goal posts — we’d just done a musical, let’s do an oratorio. That way you’re not being compared to your own work.