Few musical works have more impeccable credentials as a masterpiece than George Frederic Handel’s Messiah. It was an instant hit at its world premiere in Dublin in 1742. An oratorio–that is, a dramatic work for orchestra, chorus, and soloists that tells a religious tale–Messiah, as the title suggests, proclaims the story of the Christian redeemer. Starting with Old Testament prophecies, it depicts Jesus’ birth, death, and resurrection. The text may be merely a pious amalgam of Biblical quotation, but Handel’s score is nothing short of divine. Perfect in its musical architecture and superabundant in imaginative energy, Messiah is an astonishing procession of expressive arias and thrilling choruses. I have never yet attended a performance at which members of the audience didn’t weep with joy during the great moments, such as the famous chorus "For Unto Us a Child Is Born."

Recognizing its immense popularity, the practical-minded Handel always programmed Messiah to end his concert season. He knew it guaranteed great box office, but even the confident maestro–a German who became Britain’s most important composer–would be astonished to see the devotion it continues to enjoy. No other oratorio is so widely performed. From Brisbane to Barcelona, Messiah is presented by symphony orchestras, opera companies, church groups, universities, and amateur singing societies–usually to packed houses. This season will see at least a dozen productions in the Bay Area alone.

The only problem is that no one can agree on exactly what to perform or how to perform it. There is no single definitive version of Messiah. Handel wrote the piece for the modest forces available in provincial 18th-century Dublin. At the world premiere, he probably conducted a chorus of about 20 singers and even fewer instrumentalists. Almost every time he revived the piece, he took the opportunity to add new numbers, enlarge the orchestra, and tailor songs to the current singers. In all, he created nine different versions of the work, with no less than 43 versions of the 15 solo numbers. I won’t even attempt to explain the differences. It would take more time than summarizing the plot of The Sopranos. And they all sound great.

Deciding which version of Messiah to perform only opens up another set of issues–namely, how to perform it. A passionately vocal minority argues that any musical work should be presented as closely as possible to the way it was sung or played under the composer’s original directions. Such historical authenticity demands a similar-sized group of performers and requires antique or reconstructed period instruments rather than modern ones.

The contrasting philosophy emphasizes the right and skill of modern musicians to make small adjustments. This approach, usually called traditional performance, allows Messiah to be performed by a full modern orchestra and a large choir. Most renditions of the famed "Hallelujah" chorus use a choir far bigger than Handel had and employ instruments such as trombones and extra timpani, which were not in the score but add force to the music. The effect is indisputably thrilling, though not, a musicologist might carp, historically correct.

If the traditional approach sounds disrespectful to the composer’s intentions, it reflects the practical nature of most composers, who eagerly embrace almost any means of making their music more effective. "Authentic" music practices of Handel’s era would have to include radical change and maximum flexibility. Mozart understood this principle. When, 30 years after Handel’s death, he made his German-language arrangement of Messiah, he not only added many new instruments but also rewrote the string parts and cut the score.

My favorite traditional version is the lush late-Romantic Messiah commissioned by the English conductor Sir Thomas Beecham. Hearing Beecham’s famous 1959 recording, I find it hard to imagine that either Handel or the Messiah himself would be anything other than delighted. Beecham’s musical forces numbered at least 150 players and singers, but he probably considered them austere compared with the Victorian-era performances of his childhood, when the chorus regularly exceeded a thousand singers–about 50 times the size of Handel’s original choir. (Brits enjoyed high-decibel music long before Led Zeppelin.)

Over the past half century, the historical-authenticity movement has reshaped the classical-music world. It is no longer a rarity to hear sackbuts, serpents, citterns, basset-horns, violas da gamba, and other once-forgotten instruments in the concert hall. We can also thank the movement for a new type of ensemble that specializes in "early music" (i.e., everything before Haydn and Mozart). San Francisco’s splendid Philharmonia Baroque takes its mission so seriously that its programs describe the instruments played as well as listing their players.

But at times, the period-instrument folks become the fundamentalists of the classical-music world–insisting on hyperliteral interpretations of scores, condemning traditional approaches, and arguing over small, dubious matters of historical practice. Ideological correctness sometimes becomes an excuse for unexciting and pedantic performances, with badly balanced orchestras, thin instrumental textures, and tiny-voiced singers. I am sure that Handel often heard his music in mediocre performance, but why try to be authentic in that regard?

In addition, Handel wrote some of his best music (including the 1750 Covent Garden version of Messiah) for castrati, the male superstars of Baroque Europe. Singing in falsetto, today’s countertenors try to duplicate the legendary vocal acrobatics of this vanished race but end up sounding more like Smokey Robinson in his days with the Miracles–only a pale approximation of the original sound. Until some of the movement’s singers make the supreme sacrifice for their art, I shall doubt their commitment to authentic period practices.

There is also the matter of timing. Today Messiah is performed around Christmas, but Handel wrote it and consistently performed it for the Easter season. In most European countries in that era, opera houses were closed during Lent, because opera was considered too frivolous and worldly for the serious season of repentance. Musicians earned their keep during the pre-Easter season by performing religious works, especially oratorios. Such works were Handel’s specialty, and he designed Messiah as the climax of his profitable Lenten concerts and often scheduled the piece for Passion Week. The work clearly takes into account the audience’s devout and penitential attitude. Isn’t that spiritual and psychological component at least as important as the number of timpani? A truly "historically informed" performance would never take place in December. But such a reform, I suspect, is as unlikely as the reintroduction of castrati.

While awaiting that Messiah, you can hear Philharmonia Baroque Orchestra’s superb performances of Handel’s own versions in a three-CD set arranged to let the listener play any of the nine existing versions by using the programming feature. Although music director Nicholas McGegan uses period instruments, he beefs up the orchestra a bit, and the Berkeley Chamber Chorus numbers 42 singers plus six soloists.
Which is the real Messiah? All of them, and those offered in the Bay Area this season provide an ample selection of approaches. At the Castro Theatre, the San Francisco Gay Men’s Chorus is threatening a comic version of the "Hallelujah" chorus.

But why listen when you can sing along with organizations such as Schola Cantorum, perhaps the Bay Area’s most distinguished choral society? The Stanford Department of Music even invites us to play along with the orchestra. To hell with period instruments! Put that accordion or tenor sax in the car and head for Palo Alto.

Chosen Messiahs: Schola Cantorum (traditional), Nov. 25, Mountain View Center for the Performing Arts, 500 Castro St., (650) 903-6000. American Bach Soloists ("Historically Informed"), Dec. 18, 20, 21, Grace Cathedral, 100 California St., S.F., (650) 254-1700.