List of abbreviations; 1.Introduction; 2. Sufi Commentaries from the 4th/10th to the 7th/13th Centuries: The Rise of a Genre; 3. The Ultimate Boundary Crossing: Paradise and Hell in the Commentaries; 4. The First Boundary Crossing: Adam Descending; 5. Excursus: Embodying the Vision of God in Theology and Sufism; 6. Arin?: Declined at the Boundary?; 7. A Vision at the Utmost Boundary; 8. Conclusion; Bibliography.