Every December, choirs from around the world come together to perform Messiah by 18th-century composer George Frideric Handel.
In Australia, there is at least one performance in most capital cities.
You can usually hear Messiah broadcast on radio stations like ABC Classic in the lead up to both Christmas and Easter.
"When Handel wrote Messiah in 1741, he would never have thought it would become one of the most performed works in the canon," says Andrew ford, host of The Music Show on Radio National.
Handel didn't set out to write a Christmas classic.
But as an oratorio which tells the story of Jesus's life from birth through to his resurrection, it makes sense for the season.
In spite of a complicated and controversial history, the music's vision of a better world, coupled with memorable tunes and associations with charitable causes, makes Messiah a Christmas staple for the ages.
How Handel composed Messiah
Unlike an opera, where there are stage props and singers have to sing and act, an oratorio tells the story through words and music.
In Messiah, sometimes soloists will sing arias accompanied by the orchestra. Other times the full choir takes centre stage.
"[Messiah] is one of the most remarkable examples of the way in which words and music can work together to create more than the sum of the parts," says Charles King, a historian and author of Every Valley, a book which explores the origin story of the oratorio.
Messiah's fame is entwined with the story of its creation, King tells The Music Show.
Handel wrote Messiah in just over three weeks, by using sections of music he had already composed in the past.
It was written at a point when Handel's career in London was flagging.
"He was venerated as a composer, but [had lost his edginess]," King says.
In addition to his position as a court composer for the British monarchy, Handel turned to affluent patrons to sustain his career.
One of these patrons, Charles Gennens, was a wealthy landowner, an amateur musician and librettist.
It was Gennens who selected the biblical verses which would become the text of Messiah.
"[Gennens] suffered very deeply from what we might now call bipolar disorder or chronic depression," King says.
Gennens turned to the scriptures to create "his own kind of ladder out of this abyss," King says.
Despite Messiah's vision of a better world, it was born during one of the darkest periods of history.
"Most of the wealth of Europe was the result of slavery [and] the slave trade," Ford reminds us.
"The story of enslavement is absolutely entwined with art in this period in a way that we simply can't deny," King says.
King found that Gennens was a shareholder in the South Sea Company and Handel received portions of his salary through holding accounts in the Royal African Company, one of the major slave firms in the 1700s.
How Messiah became a Christmas tradition
Messiah's first performance took place in April 1742 in Dublin.
Gennens wasn't in attendance. He thought that Handel had "run off" to Dublin with his precious words.
The first cast of Messiah included Susannah Cibber, a stage actor and low-voiced contralto whose loveless marriage had resulted in personal scandals and legal battles.
Cibber sang one of the most dramatic and memorable arias, He Was Despised, which include the words: "A man of sorrows and acquainted with grief."
"This scandalous, notorious woman, was now standing before [700 or so people], singing about the possibility of redemption," King describes the premiere.
"It was a movie-worthy moment far before the invention of film."
The Dublin premiere was met with rave reviews.
Proceeds were donated to the release of imprisoned debtors, a hospital and an infirmary.
But the oratorio's subsequent performances in London were not warmly received.
Handel's decision to perform a sacred work in a theatre turned off many audiences from attending.
Messiah lives on partly due to its association with philanthropic causes.
From 1750, Handel offered performances of Messiah to raise funds for the Foundling Hospital, a children's home at the heart of London.
The benefit concert became an annual event and cemented Messiah as "music that was in aid of a good cause," King says.
Even though Messiah began as an Easter-themed oratorio, the music became a Christmas tradition.
"By the 1830s and 1840s, people around the world were quite accustomed to hearing it at Christmas time," King says.
Over the years, audiences have built their own traditions around the work.
An anecdote claimed King George II got to his feet during the famous Hallelujah Chorus at one of the London performances.
Audiences today still stand during that section of Messiah.
Why Messiah still resonates with audiences today
There are relatively few pieces of music that have outlived their composers for as long as Handel's Messiah.
"This piece of music has been in near continuous performance since the time it was composed [nearly 300 years ago]," King says.
Both Ford and King find the words of Messiah still quite resonant in the context of our present day.
"[Messiah] was created in a time of war, dissension, disease, ever-present death and real worry about the present state of the world," King says.
The vision of a better world makes the music timeless.
"Every performance of the Messiah begins with a promise: comfort ye, comfort ye my people," King says, referring to the first aria of the oratorio, which is taken from the biblical book of Isaiah.
This promise frames the story of Christmas and Easter which are both present in the music.
The central question of Messiah, King says, is: "How [do] you possibly have hope in a world in which all of the evidence of your senses would suggest otherwise?"
"The first step in changing the world is to re-imagine the world in a radically new way."
Hence the famous line: "every valley shall be exalted, and every mountain shall be made low."
Almost 300 years later, audiences still turn to that promise for comfort.
Sign up to the ABC Classic Newsletter
