[Attar (1145 – 1221 AD) was a Sufi, poet and theoretician of mysticism, who had a lasting influence on Iranian poetry and Sufism. Reliable information on Attar’s life is scarce but most sources agree that he was from Nishapur, a major city of medieval Khorasan, located now in northeast Iran and that he died a violent death in the massacre which Mongols inflicted on Nishapur in 1221 AD.  Attar started his career as a pharmacist and his patients used to confide their troubles with him, which affected him deeply. Finally, he abandoned his pharmacy practice and traveled throughout the Middle East, getting initiated into Sufism.
With the attack of the Mongols, the invading armies burned many books, including Attar’s. However, his major masterpiece, “The Conference of the Birds,” survived, within which he shares his famous Seven Valleys of Love or the mystic path to enlightenment. His seven valleys are: The valleys of Quest, Love, Understanding, Detachment, Unity, Bewilderment, and Death. As we journey into our own souls toward self-knowledge, he said, we also journey through the heavens because at the center of our soul lies the divine itself. Attar’s works reflect the evolution in Sufi mystic thought—the idea that the body-bound soul awaits release and return to its source in the other world, which can be experienced during the present life in mystic union attainable through inward purification. The great Sufi poet, Rumi, once said about Attar that, “Attar has traversed the seven cities of Love; We are still at the turn of one street.” 
“The Conference of the Birds” is the story of the quest for enlightenment. It is portrayed through a beautiful tale of a flock of birds and their leader, a hoopoe, the wisest of them all, who search for the legendary bird, the Simorgh. The hoopoe leads the birds, each of whom represent a human fault which prevents human kind from attaining enlightenment. After passing through the seven valleys, only 30 birds remain.  In the last valley they reach a mirror within which they see their own reflection. At that point the birds learn that they themselves are the Simorgh; the name Simorgh in Farsi means thirty (si) birds (morgh). And so they come to "understand that the majesty of the Beloved is like the sun that is reflected in a mirror and whoever looks into that mirror will also behold her own image." 
 Attar Farid-al-Din. Encyclopedia Iranica. http://www.iranicaonline.org/articles/attar-farid-al-din-poet
 "Attar of Nishapur." From Wikipedia, the free encyclopedia. CC BY SA.
 "The Conference of the Birds." From Wikipedia, the free encyclopedia. CC BY SA.
 Quoted from The Conference of the Birds by Attar, p 17-18, edited and translated by Sholeh Wolpe, W. W. Norton & Co 2017.