Buddhologist Edward Conze (1966) has proposed that similarities existed between Buddhism and Gnosticism, a term deriving from the name "Gnostics" given to a number of Christian sects. To the extent that the Buddha taught the existence of evil inclinations that remain unconquered, or that require special spiritual knowledge to conquer, Buddhism has also qualified as Gnostic.
Edward Conze claimed to have noted phenomenological commonalities between Mahayana Buddhism and Gnosticism, in his paper Buddhism and Gnosis, following an early suggestion by Isaac Jacob Schmidt.[note 1] Conze explicitly compared Mahayana Buddhism with "gnosis," that is, knowledge or insight, and not with "the Gnostics," because too little was known about the Gnostics as a social group. Based on Conze's eight similarities, Hoeller gives the following list of similarities:
According to Conze, these commonalities were not by chance, but inherent to the essence of both religions. How these similarities came into existence was unclear for Conze, but according to Verardi they may be related to the sea trade between the Roman Empire and India, which was intense at the time. Verardi further notes the similarities between the social-economic base of both Gnosticism and Buddhism, namely merchants, which both had to compete with the "great organised powers," of Rome and the Christian Church, and of the Brahmans. Both communities represented "an open economy and society lacking the defenses (and the vexations) of nomos," the law and institutions of the establishment.
Conze's suggestions were noted by Elaine Pagels as a "possibility," in the introduction to The Gnostic Gospels,[note 2] but Pagels' and Conze's suggestion has not gained academic acceptance or generated significant further study.
According to Giuseppe Tucci, Manicheism may have influenced Tantric Buddhism, while Mircea Eliade noted similarities in the symbolism of light and mystic knowledge, predating Manicheism, and possibly going back to an early common Indo-Iranian source. Verardi notes that Manicheism is the prime source for comparisons between Buddhism and Gnosticism, Manicheism representing "the same urban and mercantile ambience of which Buddhism was an expression in India." When the mercantile economy declined, with the decline of the Roman empire, Manicheism lost its support. The Manicheists were hostile to the closed society of farming and landownership, just like the Buddhism conflicted with the "non-urban world controlled by Brahman laymen."[note 3]
Mani, an Arsacid Persian by birth,[note 4] was born 216 AD in Mesopotamia (modern Iraq), then within the Persian Sassanid Empire. According to the Cologne Mani-Codex, Mani's parents were members of the Jewish Christian Gnostic sect known as the Elcesaites.
Mani believed that the teachings of Buddha, Zoroaster, and Jesus were incomplete, and that his revelations were for the entire world, calling his teachings the "Religion of Light." Following Mani's travels to the Kushan Empire[note 5] at the beginning of his proselytizing career, various Buddhist influences seem to have permeated Manichaeism:
Buddhist influences were significant in the formation of Mani's religious thought. The transmigration of souls became a Manichaean belief, and the quadripartite structure of the Manichaean community, divided between male and female monks (the "elect") and lay followers (the "hearers") who supported them, appears to be based on that of the Buddhist sangha.
Early 3rd century–4th century Christian writers such as Hippolytus and Epiphanius write about a Scythianus, who visited India around 50 CE from where he brought four books and "the doctrine of the Two Principles", in which the early church fathers describe as assigning both "good" and "evil" to God. According to Cyril of Jerusalem, Scythianus' pupil Terebinthus presented himself as a "Buddha" ("He called himself Buddas").[web 1] Terebinthus went to Palestine and Judaea ("becoming known and condemned"), and ultimately settled in Babylon, where he transmitted his teachings to a woman who left his books to a young Mani, thereby creating the foundation of Manichaeism:
But Terebinthus, his disciple in this wicked error, inherited his money and books and heresy, and came to Palestine, and becoming known and condemned in Judæa he resolved to pass into Persia: but lest he should be recognised there also by his name he changed it and called himself Buddas.
According to Willis Barnstone and Marvin Meyer, evidence of the influence of Buddhist thought on the teachings of Mani can be found throughout texts related to Mani. In the story of the Death of Mani, the Buddhist term Nirvana is being used:
It was a day of pain
and a time of sorrow
when the messenger of light
when he entered complete Nirvana