It is generally accepted that the first exponent of Sufi doctrine was the Egyptian, or Nubian, _Dhu n-Nun_ (d. 245-246), a pupil of the jurist Malik b. ´Anas, who lived at the time when there was much percolation of Hellenistic influence into the Islamic world. He was indeed nearly contemporary with `Abdullah, the son of Maymum, whose work we have already noticed. Dhu n-Nun’s teaching was recorded and systematized by al-Junayd of Baghdad (d. 297), and in it appears essential doctrine of Sufism, as of all mysticism, in the teaching of _tawhid_, the final union of the soul with God, a doctrine which is expressed in a way closely resembling the neo-Platonic teaching, save that in Sufism the means whereby this union is to be attained is not by the exercise of the intuitive faculty of reason but by piety and devotion. Still the two come very close when we find in the teachings of the later philosophers that the highest exercise of reason consists in the intuitive apprehension of the eternal verities rather than in any other activity of the intellect. Al-Junayd is stated by Jami to have been a Persian, and it is chiefly in Persian hands that the doctrines of Sufism develop and turn towards pantheism. Both agnosticism and pantheism are present practically in the later neo-Platonism; agnosticism as regards the unknowable First Cause, the God from the Agent Intellect is an emanation, a doctrine which develops in the teaching of the philosophers and of the Isma`ilians and kindred sects; but Sufi teaching centres its attention upon the knowable God, which the philosopher would describe as the Agent Intellect or Logos, and this develops more usually in a pantheistic direction. The doctrines thus developed and expressed by al-Junayd were boldly preached by his pupil, _ash-Shibli_ of Kurasan (d. 335).