Rumi, who wrote and preached in Persia during the thirteenth century, was inspired by a wandering mystic, or dervish, named Shams al-Din. Rumi's vast body of poetry includes a lengthy poem of religious mysticism, the Mathnavi, and more than three thousand lyrics and odes. A.J. Arberry, who selected four hundred of the lyrics for translation, calls Rumi "one of the world's greatest poets. In profundity of thought, inventiveness of image, and...