He continued his studies at the Helsinki Institute and played second violin in the school's string quartet as well
It was a very painful awakening when I had to admit that I had begun my training for the exacting career of a virtuoso too late.Sibelius continued to play the violin privately for over thirty years until tremors in his hands made him stop.
He started to plan his violin concerto in 1899 (the only concerto Sibelius ever wrote), and completed the work in 1904. Sibelius didn't finish the work soon enough for the soloist to study the solo part in depth, so as a result the first performance was not well received. The first version of the concerto had one of the most difficult solo violin parts ever written, so Sibelius removed the work and revised it, making it slightly less difficult and more well balanced. The concerto is in three movements:
I. Allegro moderato - The movement begins with almost inaudible figures in the strings. The soloist enters shortly after with the first theme. This theme begins to be developed immediately. The strings enter in a louder section that announces the second theme first sounded in the woodwinds. The development section leads to an extended cadenza for the soloist before the recapitulation begins. A rapid and dramatic coda tosses out the themes once more before the end of the movement.
II. Adagio di molto - This movement is in B-flat major and begins with a short introduction by the woodwinds which leads to a lyrical theme by the soloist. The middle section increases the drama of the music, after which the violin begins to sing its theme again. The movement ends in hushed beauty.
III. Allegro ma non tanto - The movement opens with a rhythmic figure in the bass, and the soloist enters with the first theme. A second theme played by the orchestra sounds like battle music complete with the snarling of muted horns. Sibelius throws all kinds of technical demands on the soloist throughout the movement, making it not only one of the most recognizable of the violin concerto literature but also one of the most difficult. The movement draws to an end with the full orchestra playing loud staccato chords while the soloist glides up and down the fingerboard.
Sibelius' realization that he was not destined to be a violin virtuoso probably frustrated and disappointed him, which may have came out in his writing for the violin concerto. He certainly had the practical and technical knowledge of the instrument if not the virtuoso technique, so he may have envisioned himself as the soloist if things would have turned out differently.