The numbering of Mendelssohn’s symphonies is a can of worms. The work his posthumous editors found it convenient to publish as Symphony No. 2 bears no structural resemblance to the four other numbered symphonies. The “Second” is, in fact, a cantata, consisting of 15 minutes of instrumental music followed by nearly an hour’s worth of sacred song for chorus, two sopranos, and a tenor, set mostly to texts from the Psalms. Mendelssohn called the piece Lobgesang (Hymn of Praise), which tells a listener just what to expect. As ever, Mendelssohn’s writing is pellucid, melodious, and exquisitely balanced. The mot juste might be “Mozartean,” if only Mozart (who does not always conform to stereotype) didn’t have a lock on it. —M.G.