This is a summary of A.D. Nock’s article about ‘Gnosticism’ that was published in 1964 after his death . It is of course somewhat outdated, but still useful for grasping Gnosticism.
1. The purpose of Nock’s article is to give an impression of Gnosticism from the viewpoint of the ethical and religious atmosphere of the Graeco-Roman world. However, Gnosticism may also fairly be related to certain human attidudes which are extremely widespread.
The first psychological factor is a preoccupation with the problem of evil. Sickness and suffering are obstinate facts which call for an explanation, that can result in for instance a dualistic worldview (influence of Zoroastrianism isn’t needed as an explanation). The second psychological factor is “a sense of alienation from man’s environment.” Even in societies that have a high degree of conformity there are moral rebels and individuals, who can feel estrangement from it. The third internal factor is a desire for special and intimate knowledge of the secrets of the universe in order to solve in some way all man’s problems.
2. These three factors are all to be found in the world in which Gnosticism took its rise. The problem of evil and a sense of estrangement can be found in Greek literature and within Judaism. Moreover, there was surely an interest in esoteric knowledge, as the popularity of the mystery cults shows.
3. Who were the ‘Gnostics’? The third century philosopher Porphyry wrote against the so-called Gnostics, who were christians and trained in the old philosophy. He regarded them as a serious menace, even in the highly educated society which he addressed. His argument, in brief, is that these Gnostics think very well of themselves and very ill of the universe. Also the earlier writer Celsus treats the Gnostics as representing a deviation within Christianity. So, Gnostics, according to pagan eyes, were intellectual Christians with a passionate dualism and with an extreme anthropocentry. Gnostics are a conglomerate which has for all its diversities a certain unity as seen from the outside.
The word gnosis has a wide range of meanings. In the New Testament Paul warns against spiritual pride in relation to special gnosis. So gnosis in Christian understanding is not without risk. However, even Clement of Alexandria calls the enlightened Christian a gnostikos.
4. The contribution of Greek thought to Christianity in its first hundred years came primarily through hellenistic Judaism. In studying the Law some hellenistic Jews made a distinction between the superficial and the deeper meaning. Moreover, the Greek philosophy was, at least in some aspects, considered acceptable among hellenistic Jews. A dualism developed, the idea of a Satanic order emerged and there was esoteric knowledge about angels and heavenly bodies. Also, many Gnostic ideas can be explained as rising from speculation about the first chapters of Genesis. Other developments in Judaism are the personification of the Wisdom as a Power of God and the angelology. These are some elements which may be thought to have contributed to the formation of Gnosticism.
5. As to the Greek components, Gnosticism can be viewed as “Platonism run wild”. Plato had written about the soul incarcerated in the body and had raised the possibility that the universe revolves under the control of two deities opposed to each other.
6. A Valentinian definition of Gnosis is: “What liberates us is not only baptism but also the kowledge of who we were, what we have become, where we were or into what we have been thrown, whither we are hurrying, whence we are being ransomed, what is birth, what is rebirth.” Parallels in Plutarch, the Chaldaic Oracles and the Hermetica are interesting, but have no indication of a cosmic Fall and a cosmic Deliverance, which is characteristic of Christian Gnosticism.
7. The Essenes and the early Christians had consciousness of the possession of special revelation. Paul speaks of a dualism of flesh and spirit and of natural and supernatural powers. Paul possessed knowledge of which he thought the Corinthians were not yet ready. Later, the waning of the eschatological expectation gave a new impetus to the emergence of Gnosticism.
8. Christians of this time (say, the second century CE) were decidedly isolated from Jews and Gentiles. This could have fueled religious speculation about the origin of evil, the Jewish God and the Jewish Law, what Jesus told his disciples after his resurrection etcetera. There was also the fact of religious lyricism with its bold imagery that possibly contributed to Gnostic speculation.
In any case, Gnosticism seems to be the aggregate of a series of individualistic responses to the religious situation. These responses were not viewed as deviationist, because orthodoxy was a gradual process and the Gnostics may have viewed their ideas as esoteric knowledge for those capable of receiving it.
9. The finds of Nag Hammadi have put more flesh on the bone structure of Gnosticism that we already possessed from the church fathers. The relation of the Gnostic texts to the New Testament seems to vindicate completely the traditional view of Gnosticism as a Christian ‘heresy’ with roots in speculative thought. To this can be added that the earliest Gnosticism probably arose around varieties of Judaism and around reaction to Judaism, with support of popular Platonism. Second, Gnosticism arose at a time when orthodoxy had not yet taken shape by conflict and contrast.
10. There was no Gnostic church. There was a Gnostic way of thinking, but no Gnostic system of thought, no specific Gnostic myth. It is unsound to reconstruct it from Manichaean and other texts and to project it back of the New Testament. It was the emergence of Jesus and the belief that he was a supernatural being who had appeared on earth which precipitated elements previously suspended in solution. Also we have to reckon with misunderstandings of Paul’s teaching. Any contribution which Persia made was at second hand, as mediated through Greek and Jewish channels.
The weakness of the Gnostics was their individualism. Eventually they couldn’t win from the growing strength of the organized church.
- ad 1. When Zoroastrianism (and Manichaeism and Mandaeism) isn’t needed as an explanation, then this does rise the suspicion of limiting the scope of research to the well known sources.
- ad 2. Was the problem of evil in Greek literature the same as in Gnostic texts? Was it really a problem? In the Greek tragedies the issues are Fate and the Wrath of the gods, not so much evil as a metaphysical problem.
- ad 3. Gnosticism as a ‘brand’ is a modern invention. Gnostics probably wouldn’t refer to themselves as ‘Gnostics’.
- ad 8-9. That Gnostics weren’t deviationist on purpose is very important and should prevent us to see them from historical viewpoint as heretics, as not “real Christians”.
- ad 10. Here Nock dismisses too quickly Persian influence, without sound arguments (however, he possibly would have improved his arguments if he had the opportunity).
 A.D. Nock, ‘Gnosticism’, Harvard Theological Review 57 (1964), 255-279.