This is a terrific book, but targeted at readers who are much more familiar with Bach’s work than the “ordinary” listener.
There are a couple of interesting approaches that the author takes. First, he is very sceptical of all generalizations about Bach, which I find very refreshing. In other words, he does not assume that every work by Bach is one of surpassing genius. Second, he pays a great deal of attention to Bach’s keyboard works, on the basis - not unreasonably - that there is more of it than there is choral music. He says that critics tend to focus on Bach’s “intent” with choral music, whereas we can never know what that intent really was.
There is much in-depth analysis of various pieces, so one needs to have a very broad familiarity with all such music. For the those who have that familiarity, this is a wonderful book. Regrettably, I don’t. I nonetheless enjoyed much of the description.