Just before she conducted her Oratorio Chorale in two vivid, rich-hued Mass settings Saturday evening at Woodfords Congregational Church in Portland, Emily Isaacson turned to the audience and offered a romantic but fully plausible theory about why composers, over the centuries, have been so attracted to the Latin Mass. The Mass, she argued, is a compact drama, its five central movements linked in a fuller story of devotion – something composers could address with the same expansiveness they might bring to a symphony or an opera.

There is a more mundane, historical reason that great Masses are so plentiful: The church, globally and locally, was for centuries a principal employer of composers, and the commissioning of new Masses was always a high priority. Monarchs and lesser nobility also were keen to have fresh Masses for their own chapels, and although that market has withered somewhat since the American and French revolutions, publishers can attest that to this day, an attractively scored Mass will find performers and listeners.

The two works on her program supported both Isaacson’s case and the more prosaic one. Antonin Dvorák, though best known for his symphonies, was asked to compose his Mass in D (1887) by a wealthy patron with a chapel on his country estate outside Prague. And Nico Muhly, a busy and prolific composer in his mid-30s, best known for his operas, instrumental and choral scores, was commissioned to write his Bright Mass with Canons (2005) by Saint Thomas Church Fifth Avenue, a large Episcopal Church in Manhattan.

Muhly’s setting has taken on a life of its own in the 11 years since he completed it. I heard it in 2008 and 2012, and it was recorded (by the Los Angeles Master Chorale, for Decca) in 2010. It fulfills one important requirement of a Mass: It stands up well to repetition, over time.

Its textures and vocal lines are clear and joyful (or, as the title puts it, bright), and full of variety. Long, winding lines that evoke liturgical works of the distant past are offset with brief, light dissonances that provide a measure of contemporary tension and, at times, theatricality. You can find hints of Minimalist figuration in the slow Benedictus, but more as a passing reference than as a propulsive technique. The Sanctus includes gracious solo lines that Muhly composed with the voices of the Saint Thomas Church boys’ choir in mind, but which were sung elegantly here by soprano Deborah Selig and mezzo-soprano Margaret Lias.

The Mulhy and Dvorák works have several points in common. Both were composed and first performed with organ accompaniment, and later orchestrated. Isaacson led the original versions, in both cases, with organist Ray Cornils providing a solid, colorful foundation. Both scores also treat the Mass’ final line – “dona nobis pacem” (“grant us peace”) – with a rising, tentative line that sounds strangely inconclusive, and more like a question than a plea.

Muhly makes a point of his score’s canons (writing in which one strand of the vocal texture is immediately imitated by a second, then a third, and so on), and the technique is a striking element, which he uses innovatively, sometimes in short bursts that create a rich, dramatic effect. Dvorák’s writing is canonic as well, but in a more straightforward, traditional way.

There are striking differences, too. Muhly skips the Credo; Dvorák includes it, and also presents a more leisurely approach to the other movements in a work more than double the length of Muhly’s. Dvorák’s score is more given to extremes: The jauntiness of the Gloria is countered by the intense introspection of the Benedictus. And Dvorák drew notably on the rhythms and melodic shapes of Czech folk music, particularly in the Credo, a call-and-response setting for solo mezzo-soprano and choir.

Dvorák’s solo writing is more expansive as well, and here tenor Gregory Zavracky and bass-baritone John David Adams filled out the roster ably. The choir, too, was in fine shape – robust and well-tuned in both works’ more outgoing passages, and appealingly gauzy and supple in the gentler writing.

Allan Kozinn is a former music critic and culture writer for The New York Times who lives in Portland. He can be contacted at:

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