Twice a year, the choir at the Unitarian Universalist Congregation of Columbia performs a musical service under the direction of Tom Benjamin.

On Sunday, Dec. 18, the choir will take on the J.S. Bach's ambitious “Magnificat,” a 25-minute choral piece that Benjamin acknowledged is more typically done by professional choirs rather than church choirs.

“Bach is demanding in so many ways,” Benjamin said. “He is uncompromising and just difficult.”

A huge Bach fan, Benjamin felt it was time to give it a go — and he believes his group is up to the task.

“We haven't done Bach in five or six years,” he said. “It was time to challenge ourselves.”

Since September, the 58-member choir has been rehearsing the piece, which tells the story of the Annunciation — when Mary is informed by an angel that she will be the mother of the Son of God.

The story is told with arias, one duet and five choral pieces, Benjamin said.

Organist Michael Adcock and Jeff Soulen, timpani, will perform with solos by Hilary Dean, soprano; Elizabeth Mondragon, mezzo-soprano, and Byron Jones, tenor.

“It is not a huge, long text,” Benjamin said of the music, describing it as celebratory.

“It is a beautiful, expressive work,” he said. “It is a fun, dance-like, high-energy, festive piece.”

The choir has a good balance, Benjamin said, and while it does not boast great numbers, its members have been working hard to prepare for Sunday's performance.

“The choir will sing their hearts out,” Benjamin said.

The performance will close Sunday's morning service, which will begin at 10 a.m. with a few service elements followed by a performance of organ music, Benjamin said. The service and performance will be held at the Owen Brown Interfaith Center, 7246 Cradlerock Way, Columbia. Admission is free.