The Teachings of Shams-i Tabrezi is a good book for the reader with some background in Islamic thought and spirituality. The advice would benefit the reader who would enjoy the interior monologue-style of Shams.
Shams, the teacher of Sufi mystic Rumi, liked to challenge his students. Their relationship is akin to that of Socrates and Plato with Shams in the role of Socrates and Rumi in the other.