His letters to his disciples are said to have commenced with the formula, "From the Lord of Lords to His slaves." His disciples wrote to him:
O Spirit of the Spirit! O highest Aim of the holy: We bear witness that Thou hast incarnated Thyself in the form of Hosain the cotton-carder (Hellaj). We flee for protection to Thee and hope in Thy mercy, O Knower of secrets.
The genuineness of these fragments has much to support it, but is not entirely beyond doubt. This much, however, is clear, that the disciples of Hellaj after his death regarded him as a divine being. Ibn Hazm, a trustworthy author who wrote only 150 years after the execution of Hellaj, says so expressly. Ghazzali, who wrote about fifty years later still, does not mention this, but shelters Hellaj from the charge of blasphemy by construing his exclamation "I am the Truth" in a pantheistic sense, and excuses it by ascribing it to an excess of love to God and to mystic ecstacy. In another place he says:
The first veil between God and His servant is His servant's soul. But the hidden depth of the human heart is divine and illuminated by light from above; for in it is mirrored the eternal Truth completely, so that it encloses the universe in itself. Now when a man turns his gaze on his own divinely illumined heart he is dazzled by the blaze of its beauty, and the expression "I am God!" easily escapes him. If from falls into error and is ruined. It is as though he had allowed himself to be misled by a little spark from the light-ocean of Godhead instead of pressing forward to get more light. The ground of this self-deception is that he in whom the Super-*natural is mirrored confuses himself with it. So the colour of a picture seen in a mirror is sometimes confounded with the mirror itself.
Hellaj was no more than the representative of an old idea, Indian in origin, which he combined with Sufism, thereby giving an entirely new direction to Islamic thought, which was important, as leading to an entirely new development of the conception of God. Even previous to Hellaj, the doctrine of incarnation had emerged in Islam. The Caliph Ali was reported to have been such, and was accordingly venerated by the Shiahs. The sect of the Khattabiyah worshipped the Imam Jafar Sadik as God. Another sect believed that the Divine Spirit had descended upon Abdallah Ibn Amr.
In Khorassan the opinion was widely spread that Abu Muslim, the great general who overturned the dynasty of the Ommeyads and set up that of the Abbasides, was an incarnation of the spirit of God. In the same province under Al Mansur, the second Abbaside Caliph, a religious leader named Ostasys professes to be an emanation of the Godhead. He collected thousands of followers, and the movement was not suppressed without much fighting. Under the Caliph Mahdi a self-styled Avatar named Ata arose, who on account of a golden mask which he continually wore was called Mokanna, or "the veiled prophet." He also had a numerous following, and held the Caliph's armies in check for several years, till in 779 a.d., being closely invested in his castle, he, with his whole harem and servants, put an end to themselves.
Towards the end of the second century after Muhammad, Babek in Persia taught the transmigration of souls and communism. His followers, named Khoramiyyah, long successfully resisted the Caliph's troops. He claimed that the soul of an ancient law-giver named "Bod" had passed into him, which meant perhaps that he wished to pass for a "Buddha."
It is well known that Shiite teachers were especially active in Persia. In the apotheosis of Ali, as well as in the cases of Abu Muslim, we find an assertion of the ideas peculiar to the Persians in pre-Islamic times. The infusion or indwelling of the Godhead in man as with the Hindu Avatars was also popular, and widely spread in Persia. In Bagdad, from the time of the early Abbasides, the Persians had exercised great influence. Shiahs were able to profess their views freely under the tolerant or rather religiously indifferent Caliph Mamoun. Bagdad early harboured within its walls a number of communities imbued with Shiah doctrine, and the Persian conception of God silently, but widely prevailed.
Hellaj, educated in the orthodox Sunni school of Junaid, which, through its laying stress on the idea of love to God, possessed rather a mystic than dogmatic character, allowed himself to be carried away by his passionate temperament into not only preaching, but practically applying to himself the above-mentioned doctrines, which though known to many, had been discreetly veiled in reserve. When once the populace have been prepared for a new idea, the mere expression of it is sufficient to act as a spark on tinder. The fatal word was spoken by Hellaj; the authorities did their duty, seized the daring innovator and put him to death in the cruel fashion of the time. But the word once spoken had been borne on the winds in all directions, and the execution of Hellaj gave a powerful impulse to the spread of his doctrine. There are periods in the lives of some nations when the longing for a martyr's crown becomes epidemic. A few years after the execution of Hellaj, a man of the people, Ibn Aby Azkyr, from the same village, Shalmaghan, where Hellaj had spent his youth, gave himself out as an incarnation of the Godhead. He was put to death with several of his followers under the reign of the Caliph Radhi, 933 a.d. A century after Hellaj an Egyptian, Ismail Darazy, from whom the Druses derive their name, proclaimed the Fatimite Caliph Hakim to be an incarnation.
How great was the influence exercised in general by those ideas for which Hellaj died a martyr's death we learn most clearly from the pages of Ghazzali, who wrote not quite two hundred years later. He says: