This eminently readable book penned by a leading interpreter of the music of Johann Sebastian Bach is an outgrowth of John Eliot Gardiner’s lifelong engagement with Bach’s sacred music—one that culminated in the conductor’s Bach Cantata Pilgrimage in the year 2000. The project commemorated the 250th anniversary of the composer’s death by performing (and recording), in the space of one year, in proper liturgical sequence, the entire surviving repertory of his church cantatas—some 200 compositions constituting in volume fully half of Bach’s extant oeuvre.

The experience equipped Gardiner with a unique perspective on the design, purpose, and stylistic evolution of the music—one that may to some extent have mimicked the composer’s own experience in its creation. The conductor has now organized his insights into a large-scale study of the composer and his works that is both a dispassionate scholarly inquiry and a passionate personal testament. Its ultimate goal is to account for what the author calls the “unfathomable genius” of Johann Sebastian Bach.

Chapters devoted to the historical and cultural contexts, and the musical traditions that shaped the composer’s worldview, fill in the necessary background. These wide-ranging surveys are well-researched, straightforward presentations of available material. Gardiner’s biographical discussions, in addition, are often quite original, indeed.

The author is clearly at pains to “humanize” his portrait of Bach and to pierce through the accumulated mythical hagiography. He wonders whether the composer was “the goody-two-shoes of legend . . . or a ruffian,” reporting that the schoolboys