What, one might wonder, is a poetic anthology of a 13th century Persian mystic, that is, a 13th century Persian mystic who is Muslim, doing on a preacher’s bookshelf? Especially one whose language is sometimes crude and sexually explicit; who mentions body parts most holy men don’t? Beyoncé and JAY-Z might name a child after him. Coldplay’s Chris Martin may find his way through divorce by reading his poems. But what is The Essential Rumi doing on a preacher’s bookshelf?