Making his Boston debut for the Celebrity Series of Boston, New York-based pianist Inon Barnatan gave us a thoughtful and personal program backed by formidable technique. It is clear that he is not interested in competing for the title of greatest virtuoso—though I believe he could—but rather he cares about sharing his depth of understanding.

The first half of Wednesday’s concert at Longy explored the influence of Bach on Franck and Barber, and the second half was devoted to one of Schubert’s final utterances, completed weeks before his death. Barnatan prefaced each composition with a few well-chosen words.

The Bach Toccata in E Minor, BWV 914 (ca. 1710), an early essay for manuals-only, transfers readily to the piano. Most striking about Barnatan’s playing, here and throughout the entire program, were his vertiginous range in dynamics from great crashing chords to the most delicate wisps of disembodied notes, and his dramatic use of sudden caesurae as structural elements. The opening notes of the Toccata were handled with a haunting intelligence, not overly ponderous but instead expectant and premonitory. The ensuing fughetta, a taste of the concluding fugue to come, worked naturally into a praeludium that built, almost as an improvisatory exploration, into the rapid cascade of notes in the fugue, a headlong flight down the rapids.

In 1884 composer and organist César Franck decided to connect his era with Bach’s. Completed the following year, the Prelude, Chorale and Fugue was premiered at the Salle Pleyel by pianist Marie Poitevin, the dedicatee. Barnatan characterized it as “one of Franck’s deeply spiritual pieces,” and played it with the “grand but sober richness” that the British critic Michael Oliver called for. The prelude opening was emotional but firmly stated, moving to ethereal pools of luminous sound. The ensuing chorale began with a funereal feel, then built to a majestic climax, the cross-over arpeggios played with a bold ripping motion, as though torn from the keyboard. The fugue, taken at a moderate pace, was powerful and emotional, with a great breadth of sonority and dynamics, ranging from fierce to gentle and flowing, ending with a beautifully evoked great peal of bells.

The Barber Piano Sonata in E-flat Minor, Op. 26 from 1949 is one of the great 20^th-century works in the form. Barnatan noted that it was premiered by Vladimir Horowitz, who convinced Barber to add the final movement. In the opening Allegro energico, Barnatan evoked a three-dimensional Escher-like view of the tonal volume as if encountered from multiple perspectives at once, a feeling of being thrown into a wild traffic of cosmic forces, striving for meaning. The Allegro was nimble and delicate, a cacophonous, fitful and massless play of flashing light, refracting and diffracting into all corners. In contrast, the Adagio mesto forced us to feel the deep inertial part of our material being, weighed down by existence. The part that clings. The part that broods. The part that hurts and laments. The part that makes its weight grow heavier, on purpose, and feels the depths of the earth in itself, like a chasm of death. The wonderful fugal allegro, evoking Mondrian’s “Broadway Boogie-Woogie” and tinged with jazz elements, revealed that space and mass are illusions, there is nothing but time, the hidden rambunctious living substance that carries everything away with it.

Following the fugal first half, the program concluded with Schubert’s great Piano Sonata in A Major, D. 959, the second of the trio of sonatas that Schubert composed in the brief window between Beethoven’s death and his own a few months later. “Beautiful, lyrical, grand and open-hearted” were the descriptors Barnatan chose. Indeed, open-heartedness is the key to understanding this work.

The opening statement was solemn, controlled, hopeful. The entire first movement juxtaposed and contrasted the sublime and the beautiful as a melodic path traced itself through a vast and threatening landscape. The wonderful Andantino started in tenderness, opening the heart to beauty and seducing it to ever more openness. Then, overexposed, the piece erupted into violent dissolution, a great fragmentation into madness, hurt and anguish. The return came as an attempt to soothe, the barcarolle now rocking gently to comfort the wound, knowing that it could not be erased. The brief Scherzo came as a valiant attempt to forget, the light and deliberately playful phrases not completely hiding the threatening reality underneath. It was all resolved in the Finale, sweet, smooth and singing mixed with waves of sadness. I had never heard the meaning of this final movement in quite the way that Barnatan made it accessible. The final return of the rondo theme was bittersweet, revealing a mature wisdom achieved through spiritual exposure in the face of annihilation. The end came as a profound farewell that left a mass of pure gold in its wake.

Acknowledging the warm applause, Barnatan gave us a brilliant reading of Mendelssohn’s Introduction and Rondo Capriccioso, Op. 14.

We must also praise the remodeling of Pickman Hall. Due to Harriet and David Griesinger, the ambience and the sound have both improved: the hall is now warm and welcoming, the music now immaculately clear. Kudos to the couple!

Leon Golub is an astrophysicist at the Center for Astrophysics in Cambridge and has been a lover of classical music for over 50 years.