Named for Rumi's spiritual teacher Shams of Tabriz, this vast lyric collection of over 40,000 verses ranks among the most translated poetry in the world. Its subject is mystical love: the soul's longing for union with the divine, rendered in ecstatic ghazals and rubā'ī (quatrains) that have lost none of their heat across seven centuries. Rumi has been the bestselling poet in America for decades, which says something about American spiritual hunger.

The case for it, the case against, and the rest of the canon open with Pro.