On a transparent May Day evening, Glissando brought its eighth season to a luminous close with French works for piano and cello. Pianist Sergey Schepkin and cellist Thomas Barth joined forces to remind a large and attentive audience at First Church Boston of the enduring power of French beauty-by-restraint.

Barth and Schepkin opened with Three Pieces for Cello and Piano by Nadia Boulanger, composed between 1911 and 1913, before the death of her sister Lili. Through careful phrasing and coordinated contrasts in dynamics, they quietly articulated Boulanger’s most adventurous gestures, hidden beneath her elegant surface forms. Similarly, Barth and Schepkin unlocked subtle experimental initiatives in Gabriel Fauré’s late Sonata No. 2 for Cello and Piano in G Minor without disrupting its timeless elegiac grandeur. They went on to liberate Claude Debussy from received ideas about “Impressionism” by suffusing his late work, the Sonata for Cello and Piano in D Minor, with its full range of heterogeneity – playfully implying that Debussy’s music serves as an open-ended exercise in diversity and inclusion. In particular, Barth beautifully emphasized the rich contrasting color achieved by various cello techniques, from bold pizzicato, harmonics, and portamento, to the airy feel of flautando, played “on the fingerboard.”

César Franck’s 1886 Violin Sonata, composed as a wedding present for violinist Eugène Ysaÿe, was arranged for cello and piano by cellist Jules Delsart with Franck’s blessing. Far from indulging in momentary mirth, Franck’s present addressed the whole compact of love and death, Eros and loss, that make up marriage. Barth took full advantage of the cello’s proximity to the male voice to create a soaring passion in the second movement and to embrace heartbreak as inevitably commingled with happiness in the Recitativo-Fantasia third movement, beautifully supported by Schepkin’s sure-footed, serene piano.

“Belle clarté, chère raison.” By citing Guillaume Apollinaire in the program notes, Schepkin put his finger on the key to French beauty-by-restraint: at every turn, lucidity, sweet and beloved rather than cruel, must accompany our attempts to escape finitude. Barth and Schepkin brought us the sound of lucidity. Like the evening light that bathes the seascape by Paul Signac that was featured on the program notes, Schepkin and Barth aimed to enlighten us gently for our own benefit, rather than to dazzle us briefly for their own profit. Glissando, Boston’s best kept secret, brings together a family of musicians and music lovers who genuinely communicate with one another and with the repertoire—far from the madding crowd.

Anne Davenport is a scholar of early modern theology and philosophy. She has published books on medieval theories of infinity and Descartes. Her most recent book is “Suspicious Moderate” on the life and works of the 17^th-century English Franciscan, Francis à Sancta Clara.