The Naassenes (Greek Naasseni, possibly from Hebrew נָחָשׁ naḥaš, snake) were a Christian Gnostic sect known only through the writings of Hippolytus of Rome.
The Naassenes claimed to have been taught their doctrines by Mariamne, a disciple of James the Just. The retention of the Hebrew form shows that their beliefs may represent the earliest stages of Gnosticism. Hippolytus regards them as among the first to be called simply "Gnostics", alleging that they alone have sounded the depths of knowledge.
The Naassenes had one or more books out of which Hippolytus of Rome largely quotes in the Philosophumena, which professed to contain heads of discourses communicated by James, the brother of Jesus, to Mariamne. They contained treatises of a mystical, philosophic, devotional, and exegetical character, rather than a cosmological exposition. A very interesting feature of the book seems to have been the specimens it gave of Ophite hymnology.
The writer (or writers) is possibly Greek. He does indeed use the Hebrew words Naas and Caulacau, but these words had already passed into the common Gnostic vocabulary so as to become known to many unacquainted with Hebrew. He shows a great knowledge of the religious mysteries of various nations. For instance, he dilates much on the Phrygian rites, and the whole section seems to be a commentary on a hymn to the Phrygian Attis.
The Naassenes so far agreed with other Ophites that they gave to the first principle the names First Man and Son of Man, calling him in their hymns Adamas:
The First Man (Protanthropos, Adamas); the fundamental being before its differentiation into individuals (cf. Adam Kadmon).
The Son of Man; the same being after it has been individualized into existing things and thus sunk into matter.
Instead, however, of retaining the female principle of the Syrian Ophites, they represented their "Man" as androgynous; and hence one of their hymns runs "From thee, father, through thee, mother, the two immortal names." They declared that "the beginning of Perfection is the gnosis of Man, but the gnosis of God is perfected Perfection.