Think of it as a “Messiah’ Sing-In for Dummies.”

The 34th annual Christmas Carol Sing-In returns to the Ogden Tabernacle this weekend, offering those of us who love to sing — but might not be particularly great at it — a chance to take part in a massive choir made up of hundreds of voices.

The idea of a Christmas carol sing-in came to local music lover Jerry Harrop in the early 1980s. Just two years earlier, in 1979, then-Weber State College choral director Lyneer C. Smith and a few others had formed an annual “Messiah” sing-in event that allowed music lovers to dust off their George Frideric Handel sheet music and gather to sing the challenging 18th-century oratorio.

Which got Harrop to thinking.

“The ‘Messiah’ Sing-In is wonderful — especially for those who know how to read music, or have done choir in high school or college,” Harrop said.

But what about everyone else, for whom the sum total of their holiday music experience may be singing “Silent Night” at church?

“I thought, ‘What about the Christmas carols — those songs that a lot of people have heard in their lives from the time they were born?’” Harrop windered. “They would at least know the melody of those songs, so why not do something for them.”

So Harrop organized the first Christmas Carol Sing-In in 1981. Over the years, the event has always been held on the third Sunday in December — except for a four-year hiatus while the Ogden Temple and Tabernacle were being renovated.

Harrop said the size of the choir varies from year to year, depending largely on the weather.

“We’ve had everything from 47 people — that was the year, many years ago, when we had a terrible snowstorm in Ogden and the power was out for hours and hours — to over 1,400 people show up at the sing-in,” Harrop said.

This year’s sing-in will feature about 17 carols, with a focus on the spiritual side of the holiday, according to Harrop. It will feature well-known carols like “Hark the Herald Angels Sing,” “O Come, All Ye Faithful,” and “Joy to the World.”

“We used to be able to sing some of these songs in the schools, now we wouldn’t dare because they are the songs that tell about the people in the Bible,” Harrop said.

He said the participatory concert features music that tells the story of Mary, Joseph, the baby Jesus and others in the story of the first Christmas, rather than songs about “Santa Claus and reindeer.”

“It’s a spiritual, uplifting thing,” Harrop said. “And there’s no charge to attend.”

Six of the carols will be prefaced by short histories of the songs and their composers. These interludes will be read by Casey Coleman, Diane Earnshaw and Bunny Aiken Johnson, according to Harrop.

“When people sing that much — and they’re not used to singing that much — they need a little chance to catch their breath before the next one goes off,” he said.

The organist for the sing-in — as it has been for the 33 previous concerts — will be Harrop’s brother, Lowell Marriott Harrop. Guest conductor for this year’s concert will be Cory Evans, director of choral activities at Utah State University in Logan.

The Harrop brothers finance the annual sing-in, keeping it free for participants. The program will last about an hour and 20 minutes, and organizers recommend Sunday dress.

“Most people do dress up, but there’s not a dress code,” Harrop said.

And if you happen to be a little shaky on the second and third verses of “O Little Town of Bethlehem”? Harrop says not to worry. They’ll have the words to the songs projected on the wall to either side of the organ pipes.

Harrop said the yearly event is always an incredible experience for the people of Ogden.

“It’s a marvelous sound with the pipe organ, and then you add the people’s voices,” he said. “It really is a joyful experience — you can hear it in your heart.”