_Al-Husayn b. Mansur al-Hallaj_ (d. 309) was a fellow-student of ash-Shibli, and shows Sufism as allied with extremely unorthodox elements. He was of Zoroastrian descent and closely in touch with the Qarmatians, and seems to have held those doctrines which are usually associated with the _ghulat_ or extreme Shi`ites, such as transmigration, incarnation, etc. He was put to death as a heretic for declaring “I am the truth”, thus identifying himself with God. The accounts given of him show great differences of opinion: for the most part the earlier historians, approaching the subject from an orthodox stand-point, represent him as a wily conjurer who by pretended miracles gained a number of adherents, but later Sufi writers regard him as a saint and martyr who suffered because he disclosed the great secret of the union between the soul and God. The doctrine of _hulul_, or the incarnation of God in the human body, was one of the cardinal tenets of the _ghulat_. According to al-Hallaj, man is essentially divine because he was created by God in his own image, and that is why, in Qur. 2, 32, God bids the angels worship Adam. In _hulul_, which is treated as _tawhid_ taking place in this present life, the deity of God enters the human soul in the same way that the soul at birth enters the body. This teaching is a fusion of the old pre-Islamic Persian beliefs as to incarnation and the philosophical theories of neo-Platonism, of the Intellect or rational soul or spirit, as it is more commonly called by English writers, the part added to the animal soul is an emanation from the Agent Intellect, to which it will ultimately return and with which it will be united (cf. Massignon: _Kitab al-Tawasin_, Paris, 1913). This is an extremely interesting illustration of the fusion of oriental and Hellenistic elements in Sufism, and shows that the theoretical doctrines of Sufism, whatever they may have borrowed from Persia and India, receive their interpretative hypotheses from neo-Platonism. It is interesting also as shewing in the person of al-Hallaj a meeting-point between the Sufi and the philosopher of the Isma`ilian school. Very similar was the teaching of Abu Yazid or Bayazid of Bistam (d. 260), who was also of Zoroastrian descent. The pantheistic element is very clearly defined: “God,” he said, “is an unfathomable ocean”; he himself was the throne of God, the preserved Tablet, the Pen, the Word--all images taken from the Qur´an--Abraham, Moses, Jesus, and Gabriel, for all who obtain true being are absorbed into God and become one with God.