As holiday perennials go, performances of George Frideric Handel's Messiah are almost as ubiquitous as the Christmas tree. Like the beloved tannenbaum, no two Messiahs are the same.

There are obvious differences in Lexington-area Messiah performances — venues, musician choices — but the biggest variance might be in the edit.

"Messiah runs nearly three hours, even at Baroque tempos," says Lexington Philharmonic music director Scott Terrell, "so it's rare you see anyone perform the whole thing."

Lexington Singers director Jefferson Johnson says, "Handel's large pieces, like his oratorios and his operas, benefit from reinvention for the modern ear and modern audience. They're just too long."

So the directors, both of whom have Messiah performances next weekend, are presenting edited versions of the masterwork. (A third Messiah, by the choirs at Christ Church Cathedral, was performed Friday.)

Some may think taking a red pen or a virtual Exacto knife to one of the masters is profane, but it is actually done all the time to dance pieces, literature, plays by William Shakespeare and operas by iconic composers.

For Terrell, who will lead the Philharmonic on Saturday at the Cathedral of Christ the King, editing Messiah is part of the fun of presenting it.

"I haven't ever done it the same way from year to year," Terrell says. "And I have found that over the years, certain ones work better than others, and that some combinations work better than others. This year, we're going to do a little bit more from Part II than we've done before, and we'll see how that goes.

"I think one reason why the piece can survive all these different iterations is he did a brilliant job of allowing for these transitions to be relatively smooth and to make it work."

Messiah is divided into three parts: the birth of Jesus or the "Christmas" portion, the passion, and the resurrection or the "Easter" portion. Terrell says that since the work is traditionally done at Christmastime, he usually presents the Christmas portion in its entirety. Then, he pieces together parts of the second and third acts to make a solid 80-minute, intermissionless work.

Terrell says he likes to do Messiah in one act. "I don't like to interrupt the flow once it gets going," he said.

Since Johnson began conducting Messiah performances (first with the Philharmonic in 2008 and '09 and then with the Lexington Singers since 2010), he has remained loyal to a version that should be familiar to Lexington classical music fans: former Philharmonic music director George Zack's edit.

"I thought George did a masterful job of selecting movements that had ebb and flow, peaks and valleys and a nice contrast between slow and fast tempos, and also spreading the choruses around," says Johnson, who will conduct the Lexington Singers at the Singletary Center for the Arts on Dec. 16. "I tried to improve on it, and I can't. We do the entire Christmas portion, and then he selected the key movements and most dramatic portions of the second and third parts of Messiah."

Johnson says directing the Singers, he has been tempted to do things like present Messiah split between the Christmas and Easter seasons. But he notes that the Christmas portion alone would be short, "and then you have half a concert."

Rather than hacking it in half, Johnson says, plotting out Messiah is akin to editing a novel.

"We end the way Handel intended and begin the way he intended," Johnson says. "This version chips away all the unnecessary parts.

"But looking back at programs of other Messiahs, there are all sorts of different ways to do it."

The major conundrum, Johnson says, is where to place the Hallelujah chorus, which in the full-length Messiah is at the end of the second act. Many versions move the iconic chorus, during which audiences traditionally stand, to the end of the concert. Johnson says he even participated in a version at Michigan State University that incorporated Hallelujah twice, before the intermission and then at the end of the performance.

Cooking up a new version each year, Terrell says, there are important considerations, such as the dramatic flow of the work, key signatures and their relationship to one another, and the distribution of soloists and choral parts.

He says Handel originally structured the work so that the transitions in key signatures "would be very pleasing to the ear." He wants to preserve that.

But Terrell isn't interested in a "definitive" Messiah.

"The definitive Messiah would be doing it all," Terrell says. "And rarely does anyone want to sit through all of that. That's why each performance can be truly unique."

Rich Copley: (859) 231-3217. Twitter: @copiousnotes. Blog: copiousnotes.bloginky.com.