St. Mary Schola, an enterprising early music group founded six years ago in Falmouth, presented a fascinatingly antiquarian glimpse of the Christmas repertory in “Today’s Light – Lux Hodie,” the program it performed Friday evening at the Cathedral Church of St. Luke in Portland. Unusual among Christmas concerts these days, it offered works that are focused exclusively on the holiday’s religious roots, with no paeans to wintry cheer, snowmen, reindeer or mythical bearded characters.

The concert was, in fact, presented almost in the form of a service, with readings, by the Rev. David Illingworth, between most of the musical selections. The texts were drawn from the works of secular poets’ reflections on Christmas, and included Kenneth Patchen’s “Candles, Mary,” John Milton’s “On the Morning of Christ’s Nativity,” Thomas Merton’s “The Holy Child’s Song,” Henry Vaughan’s “Christ’s Nativity” and Richard Wilbur’s “A Christmas Hymn.”

That’s not to suggest that the program was devoid of revelry. The ensemble began with excerpts from “La Messe des Fous,” a 13th-century liturgical drama for the Feast of Fools, during which young clerics lead a lighthearted service with a procession led by a donkey. The feast, which was popular in northern France, took place shortly after Christmas, and though its original intent may have been to commemorate the flight into Egypt (on a donkey), church officials had misgivings about the sometimes violent, bawdy celebrations, and finally banned the feast in 1431.

The selections St. Mary Schola presented included nothing that could be regarded as unseemly. Indeed, the ensemble moved without pause from “Haec Est Clara Dies” (“Behold This Bright Day”), a spirited section of the “Messe,” to the sweetly harmonized “O Virgo Splendens” (“O Resplendent Virgin”), a penitential supplication to the Madonna from the “Llibre Vermell de Montserrat,” a collection of poems and songs compiled at the Benedictine abbey of Montserrat in the late 14th century.

The performances of these early pieces were finely wrought, but the ensemble’s real strengths emerged with the richer music of the Renaissance, in Jacobus Clemens Non Papa’s “O Maria Vernans Rosa” (“O Mary, Rose of Spring”). Here, the ensemble’s 11 singers, led by Bruce Fithian, produced a magnificently blended, irresistibly smooth sound, maintained in Claudio Monteverdi’s “Cantate Domino” (“Sing to the Lord”) and William Byrd’s “This Day Christ Was Born.” That blend frayed slightly at the start of Jacob Handl’s “Jerusalem, Gaude Gaudio Magno” (“Jerusalem, Rejoice With Great Joy”), but the ensemble recovered quickly.

Several of the selections featured soloists from within the ensemble. A striking Monteverdi duet, “Venite, Venite Sitientes ad Aquas Domine” (“O Come, O Come to the Waters All Who Thirst for the Lord”), was given a tepid rendering by Christine Letcher and Andrea Graichen, but Fithian noted that Graichen substituted for an ill singerl. She was heard to much better effect in Byrd’s “An Earthly Tree, a Heavenly Fruit,” along with Erin Chenard.

In the program’s second half, which was devoted to a Baroque setting, Abra Mueller and Martin Lescault were the well-matched soloists in Bach’s “Ruft und Fleht den Himmel An” (“Call and Pray to Heaven,” from Cantata 63), and Molly Harmon gave a solid, shapely reading of “Stein, der Über All Schätz” (“Rock, Superior to All Gems”), a soprano aria from Bach’s Cantata 152, to which Scott Budde contributed a lovely account of the obbligato recorder line.

The concert ended with two attractive examples of the flowing French Baroque style by Marc-Antoine Charpentier. “In Nativitatem Domini Canticum” (“The Christmas Song”), solo voices – Lescault, Mueller, Chenard and John D. Adams, a powerful bass – alternated with ensemble responses. And in an ecstatic “Magnificat” setting, Adams, Lescault and a countertenor, Christopher Garrepy, sang the solo sections with the full chorus concluding each of the work’s sections. Several of the pieces were accompanied by the schola’s period instrument ensemble, led by Fithian from a chamber organ.

The concert will be repeated Sunday at the Episcopal Church of St. Mary in Falmouth. The ensemble’s next concert is a performance of Handel’s “Dixit Dominus” at the Cathedral of the Immaculate Conception in Portland on March 8; the Cathedral of St. Luke in Portland on March 11, and the Church of St. Mary in Falmouth on March 13.

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

allankozinn@gmail.com

Twitter: kozinn