As twilight deepened Saturday night, listeners made their way from every direction along the spokelike paths of Trinity Park to the Oak Bluffs Tabernacle for the annual summer concert by the Island Community Chorus. Marking 25 years of crowd-pleasing performances, this holiday show was also Peter Boak’s final concert as director of the group.

“This is a very, very special concert,” said chorus president Pam Butterick, as she welcomed the audience of more than 300 who gathered beneath the Tabernacle’s tiered roof to hear Mr. Boak lead the group one last time.

“It’s a bittersweet night for us, but we are overjoyed at the wonderful memories that we’ve had from this quarter-century that Peter has been with us,” Ms. Butterick said.

Summer show packed the Tabernacle in Oak Bluffs. — Ray Ewing

In addition to the annual summer and Christmas concerts at the Tabernacle and Old Whaling Church, Mr. Boak has led the chorus on overseas tours and through increasingly complex spring performances including Brahms’ German Requiem (in English) and a new cantata by composer Thomas LaVoy, based on the writings of Island “chicken lady” Nancy Luce.

After originally announcing his retirement in January, 2020, Mr. Boak postponed his departure until after the singers could emerge from Covid restrictions.

“He gave us two more years,” Ms. Butterick told Saturday’s audience.

Taking the stage to enthusiastic applause, Mr. Boak kept his own remarks brief and to the point for most of the hour-long concert.

Jenny Friedman performing a solo number. — Ray Ewing

“It’s always great to hear you sing along with the chorus,” he told the audience, after opening the show with the national anthem.

Listeners got their chance to join in another patriotic song later in the concert, with a stirring My Country ’Tis of Thee divided into verses for men, women and everyone in the Tabernacle.

For the rest of his final program with the chorus, Mr. Boak chose a mix of classical and popular music from both sides of the Atlantic, including gospel hymns by Charles Albert Tindley and Andraé Crouch.

“It’s one of the pieces that has been in our repertoire the longest. So here we go one more time,” Mr. Boak said of Mr. Crouch’s Soon and Very Soon, composed in 1976.

In a nod to the season that brought intrigued ice-cream-licking families to linger and listen outside the Tabernacle’s lights, the chorus also sang Summertime, from the Gershwins’ opera Porgy and Bess, and the Scottish folk ballad Wild Mountain Thyme.

Sleepy Man, a tender aria from Alfred Uhry’s musical The Robber Bridegroom, featured soprano Jenny Friedman in a performance that left a brief hush before the audience burst into applause.

Curtain call for the chorus. — Ray Ewing

“You see why we had to have that song?” Mr. Boak said.

Soprano Molly Conole also had a solo role in the concert, but not as a singer. An accomplished flutist, Ms. Conole played in a trio with frequent chorus guests Brian Weiland, on drums, and violinist Rebecca Laird on the Celtic-inspired, uptempo Riversong.

Mr. Boak also chose two modern choral works. While less well-known than the gospel, patriotic and show-business numbers in the program, each provided some of the evening’s best listening. Morton Lauridsen’s Dirait-on, a setting of lyrics in French by Austrian poet Rainer Maria Rilke, is the composer’s dreamy take on a folk song. Here again, the chorus’s performance left audience members momentarily silent in appreciation.

But it was Norwegian composer Kim André Arneson’s Flight Song, with words by Euan Tait, that most fit the occasion. Written for the famed choir at St. Olaf College in Minnesota, Mr. Boak explained as he introduced the piece, it honors the relationship between chorus and director.

“All we are, we have found in song: You have drawn this song from us,” the Island Community Chorus sang.

The evening ended with a rollicking arrangement of Buffalo Gals, featuring both the chorus’s longtime accompanist L. Garrett Brown and his brother Wesley Brown — once Mr. Boak’s roommate at Westminster Choir College in New Jersey, and now the organist at Trinity Episcopal Church in Oak Bluffs — at the piano, in a four-handed accompaniment that would not have been out of place in an Oak Bluffs parlor during the mid-19th century.

Standing ovation from the crowd. — Ray Ewing

But first, Mr. Boak had some parting words for the audience.

“What a privilege it’s been to be in front of this group for 25 years, and in front of you for 25 years,” he said. “I cannot thank you enough.”

About 800 people have been members of the chorus over the years, Mr. Boak continued, and about 10 of the singers on stage Saturday night have been with the group for the entire quarter-century.

“I step down after the final notes of this song, but the chorus is going on,” he said.

“Next summer I’m going to be out there with you, so save me a seat,” he added, as the audience erupted in whooping cheers and applause.

Saturday’s concert also marked the 20th anniversary of the Peter Boak Award, a scholarship established in 2002 for Islanders graduating from high school who are continuing their music studies in college. This year’s recipient is Benedict Yancey, a singer and actor who appeared as Jean Valjean in the regional high school’s recent production of Les Misérables.

Mr. Boak remains in his position as minister of music at the Federated Church in Edgartown, where he celebrated his 25th anniversary last fall.

More information about the Island Community Chorus is posted at islandcommunitychorus.com.