Possible Clues:

• Persian poet
• Persian poet who wrote the "Spiritual Couplets"
• 13th-century Persian poet and mystic
• Persian poet who wrote 'The Guest House'
• Persian poet whose name sounds like "roomy"
• Popular poet, expansive by all accounts
• Mystic Persian poet
• 13th-century Persian mystic who is one of the best-selling poets in the U.S
• Popular poet starts to rhapsodise using mystical imagery
• Thirteenth-century Persian poet