Rachel Barton Pine was stellar on Bach sonatas and partitas Sunday at the National Gallery. (Lisa-Marie Mazzucco)

Violinists often take on a movement or two of a Bach sonata or partita to show off their chops. Unaccompanied, the violinist is out there alone to roll out harmonies and contrapuntal textures that you’d think would be impossible with a bow on a single stringed instrument. Usually, what is most impressive about such efforts is the athleticism and agility of the violinist. Who hasn’t wondered at the technique involved in a performance of the famous “Chaconne”?

At the National Gallery on Sunday, violinist Rachel Barton Pine aimed the spotlight not at her own dazzling technique but rather at the music in as astonishing and joyful a performance of all three sonatas and three partitas as I’ve ever heard. There was none of the rhythmic distortion, the little extra time that so many violinists steal to bridge the bow across all four strings and is excused as a stylistic nicety; no posturing at the climax of a series of impossibly fast ornamental turns and no exaggerated phrasing or tempos in the graceful slower dance movements — just elegant ideas realized elegantly.

What Pine communicated was pure Bach, his pleasure in working out musical ideas, his architectural structures large and small and his reverence for both the struggle and the peace that music can offer. Her talks about each piece, consummate scholarship delivered with humor and modesty, was an additional ornament to her performance.

The quick “doubles” that ended each movement of the First Partita were playful, charged with light rhythmic energy, while the repeated bass of the Second Sonata’s Andante had a comfortable weight that supported but never dragged the two meditative voices above it. There was momentum let loose in the C Major Sonata’s Allegro that was almost as irresistible as the lightninglike ornamental filigrees revealed in the startling clarity of her reading of the “Chaconne.” For the last partita, Pine shifted her grip up on the Baroque bow she was using, changing its balance and imparting an extra airiness and grace to this final set of lighthearted dances, a sunny end to a 2 1/2 -hour musical marathon.