Secular devotional books

Back in my evangelical youth group days, we were encouraged to “do devotions,” which consisted in reading short meditations paired with biblical passages. This paradigm has stuck with me. When I was studying German, for instance, I used Benjamin’s “Theses on the Philosophy of History” as my reading text for a while, and I referred to my method — reading over one “thesis” per day and going through it several times until I didn’t have to look up words and could get the sensation of “just reading” — as a “devotional” method.

It seems to me that there are some boks that one might call secular or philosophical “devotional books.” Some that leap to mind are Adorno’s Minima Moralia and Agamben’s Coming Community or Idea of Prose. Can we think of any others? (Perhaps some of Nietzsche’s more aphoristic works, for instance.)