The fourth annual Barroom Messiah returns to the downtown FOG Café & Bar, 328 Main St., Saturday, Dec. 15. Those who want to sing are encouraged to come to the brush-up rehearsal that begins at 2 p.m. The sing itself will begin at 4:30 p.m.

According to series founder Charles Brown, Barroom Messiah is an attempt to take Handel’s oratorio out of the church or concert hall and perform it in a comfortable public house setting.

“We encourage people to treat it like opera and applaud the soloists, and people are welcome to sing the choruses,” he said a week before the Midcoast sing.

Earlier this month, Brown, music director at Rockport’s Nativity Lutheran Church, assembled a group of soloists and a small string orchestra for a Barroom Messiah sing at Portland’s Blue. The same musicians will be part of the FOG sing; Brown conducts, as well as playing harpsichord/keyboard.

Chorus members are encouraged to bring their “Messiah” scores if they have them; there will be some on hand, as well. Listeners are welcome to come hear the performance, which will run just over an hour.

“We are only doing Part I, which contains the Christmas story. We end with the [Part II] ‘Hallelujah’ Chorus because, why not,” Brown said.

Barroom Messiah has become a part of many people’s holiday celebration, he added. There is no admission charge, but donations are encouraged to help pay the soloists and orchestra.