Among the glories of Boston’s musical life is the city’s rich choral tradition. Singing has been a preferred way of making music here from the time of the first European arrivals. Several choral ensembles currently active in Boston trace their origin back to the 19^th century, including the Handel & Haydn Society from early in the century to the Boston Cecilia at the other end.

This year Musica Sacra is celebrating its 50^th anniversary, and though a “mere” half century may seem like a modest duration in the face of an organization (H&H) completing its second century, by the standards of the experience of any one singer (or audience member), 50 years is a long time for an organization to grow, develop, stabilize, and flourish — a period well worth celebrating. There is an additional reason for festivity on this occasion, because Musica Sacra’s highly regarded director, Mary Beekman, is also celebrating 30 years at the head of the ensemble — an experience scarcely unknown among Boston’s durable cast of leading choral conductors, but nonetheless worthy of special attention.

To begin its 50^th season, Musica Sacra chose one of the best-loved works of the romantic choral repertory, Johannes Brahms’s German Requiem, the work with which Brahms himself first attained a general success, and one that quickly became a standard repertory work for chorus and orchestra.  Since Musica Sacra has  always been a chorus of moderate size (27 members were listed in the program for this concert), the organization chose to invite the somewhat larger Boston Cecilia (47 members, of whom one was a member of both groups) to join them in the performance with orchestra.

The program for the afternoon also included two works for unaccompanied chorus, presented as “Before” Brahms and “Beyond” him.  These two short pieces, taking up less than a quarter hour of performing time, opened the program (with the orchestra offstage); then, after a short break to bring on the orchestra, the Brahms work continued without intermission.

The opening piece was a special touch:  A setting of the same text that Brahms set in the last movement of the German Requiem in an a cappella version by one of his greatest forebears, Heinrich Schütz. Brahms, one of the most historically knowledgeable of composers, certainly knew the Schütz setting, which might, indeed, have suggested the Biblical passage (Revelation14:13) for his own work. It was performed elegantly by the Musica Sacra singers, with a fine balance of voices and a clear, expressive presentation of the text.

Then the Musica Sacra singers were joined by the Boston Cecilia singers for a modern choral work sung unaccompanied, Sleep, set by the young composer Eric Whitacre, who has in recent years composed a series of choral works of lush, expressive harmonies and rich choral sonorities. The extraordinary blend of the voices gave luminous expression to Whitacre’s harmonic colors.

The pièce de résistance of the afternoon was marked by the same qualities of clarity, balance, and expression. From the opening movement’s “Selig sind, die da Leid tragen,” the singers shaped their lines with superb attention to the composer’s demands with regard to swelling crescendos and diminuendos, which can look finicky  on the page, but which bring the phrases vividly to life when presented as naturally as they were here. A minor quibble in the opening movement was that the small number of lower strings offered a slightly frail sonority from Brahms’s calm opening measures (the violins—a larger group—are silent until the beginning of the second movement).  But once the entire orchestra was taking part, the balance worked better and supported the chorus very creditably.

Mary Beekman presented an overall shaping of the work’s feeling of motion, from the weary, dragging sound of the second movement’s lament that “all flesh is as grass” to the very energetic explosion of the “last trumpet” in movement six, bringing with it the exciting, high-energy cry “Death, where is your sting?” Along the way baritone Dana Whiteside was suitably urgent in the tense anticipation of death and the last judgement (in the third and sixth movements), while Emily Hindrichs floated the long-breathed, high soprano lines of the movement that Brahms added in memory of his own mother after completing the rest of the piece, and she did so with superb (and welcome) diction.

The closing measures of the score (which echo the very opening, though  now with the full orchestra and brighter lyricism, brought the afternoon to a touching, tranquil conclusion, that led — after an extended moment of breathless silence from the audience — to a thoroughly well-deserved round of applause.

Steven Ledbetter, a free-lance writer and lecturer on music, was program annotator for the Boston Symphony Orchestra from 1979 to 1997. He is a graduate of Pomona College and got his PhD in Musicology from New York University.