Gnosticism has as one of its tenets a belief that there are pleroma and emanations from God, beings godlike and later angelic...one after another, each inferior down the line. One train of thought was that one of these lesser deities was the Old Testament God who created the material world and is responsible for its evils. From wikipedia: Gnosticism (from Ancient Greek: γνωστικός gnostikos, "learned", from γνῶσις gnōsis, knowledge) describes a collection of ancient religions whose adherents shunned the material world – which they viewed as created by the demiurge – and embraced the spiritual world. Gnostic ideas influenced many ancient religions that teach that gnosis (variously interpreted as knowledge, enlightenment, salvation, emancipation or 'oneness with God') may be reached by practicing philanthropy to the point of personal poverty, sexual abstinence (as far as possible for hearers, entirely for initiates) and diligently searching for wisdom by helping others. However, practices varied among those who were Gnostic.
In Gnosticism, the world of the demiurge is represented by the lower world, which is associated with matter, flesh, time and, more particularly, an imperfect, ephemeral world. The world of God is represented by the upper world and is associated with the soul and perfection. The world of God is eternal and not part of the physical. It is impalpable and timeless.
Gnostics believe that people have a spiritual inner spark that, if awakened, connects them to deity in some manner (whether to a god or their inner discovery of self deification). They tend to believe Jesus was just a good man and teacher in whom the “spirit” of Christ dwelt. Gnostics taught that matter is inherently evil and that humans should seek salvation apart from the material world through a special knowledge.
Many of them taught that Jesus came merely as a spirit being rather than a flesh & blood man (thus denying the incarnation), which John the Apostle sought to counter when he wrote:
"...every spirit that confesseth not that Jesus Christ is come in the flesh is not of God: and this is that spirit of antichrist, whereof ye have heard that it should come; and even now already is it in the world..." (1 John 4:3)
John was careful to tell of Him whom he and his fellow disciples saw, and touched, and even handled, the Word of life. This was in contrast to the gnostic spirtualizing of his person, which lowered him from absolute Deity, to merely being someone who had achieved what they seek through the hidden knowledge.
The precise definition of gnosticism is difficult, but found its basis in an assumed superior knowledge, and exaltation of those "in the know" who arrived at a more enlightened place than others. It was also very flexible and able to amalgamate various religious systems. It may take the outer forms and rituals of liturgical christendom (which should be a clue of a gateway for the error-ie...ritual), but therein they change its essential content. It was also seen as doing the opposite and avoiding the sacramental tendencies that developed in early christendom. It was flexible. The psychological, and intellectual element was prevalent. It manifested in the exaltation of the person who has attained to the higher knowledge. Such a person was approaching and discovering their own inner divinity.
Sin and salvation are generally denied in the gnostic system, in that it seeks to help man escape the material world and its hindrances apart from the truths of scripture. A strong desire to break free from the felt bondage, loses the biblical explanation for such 'groanings' (Romans 8) in that is fails to recognize the fall of man, and thus the presence of sin.
Paul in his epistle to the Colossians seems to anticipate & confront early workings of gnostic thought which John later fights. In Col 1:9-10 Paul writes:
"...For this cause we also, since the day we heard it, do not cease to pray for you, and to desire that ye might be filled with the knowledge of his will in all wisdom and spiritual understanding; that ye might walk worthy of the Lord unto all pleasing, being fruitful in every good work, and increasing in the knowledge of God..."
Notice his emphasis upon true knowledge, and true understanding, as if to refute those bringing into Colosse their own "full knowledge". He goes on then to explain that all that man needs, without exception is found outside man, rather than in some inner spark and needed enlightenment...and that true knowledge is found in the person of Christ, who was God incarnate.
Colossians 2:2-4 "...that their hearts might be comforted, being knit together in love, and unto all riches of the full assurance of understanding, to the acknowledgement of the mystery of God, and of the Father, and of Christ; in whom are hid all the treasures of wisdom and knowledge. And this I say, lest any man should beguile you with enticing words..."
Ultimately, gnosticism sees Christ merely as a Liberator or Revealer, rather than a Savior and a Judge. And herein is the essence of the problem. As a system, the gnostic thought tends to the elevation and exaltation of man, and of necessity lowers the Lord Jesus Christ to that esoteric level. This could have been on Paul's mind when he wrote this staggering verse:
Colossians 2:9 For in him dwelleth all the fulness of the Godhead bodily.
There are many inroads to gnostic thinking today that may not even be fully categorized as gnostic. Herea are a few examples where a type of knowledge is exalted, or pre-gnostic thinking is found, and this is as diverse and broad in scope as was.....ancient gnosticism:
The Roman Catholic ritual, Mariology, and its mysticism.
Hebrew Roots Movement's insistence on use of Hebrew language & terminology - a super knowledge (The Local Church of Witness Lee has interesting parallels in their unique language & jargon)
Tongues, Healings, and Positive Confession of the Charismatic/Pentecostals
Positive thinking ideas, both religious and secular and increasingly the healthcare sphere.
All modern movements towards Buddhism have a gnostic flavor, whether yoga, philanthropy (as a means to enlightenment), "paying it forward", yin and yang, and so forth.
Resistance to what is viewed as fundamental and organized "religion" and even that which is seen as institutional.
The denial of the authority of scripture, the incarnation of Christ, his vicarious substitutionary death.
Renewed interest in ancient gnostic literature, especially that which was rejected by the early church. The Da Vinci Code for example.
An increasing interest in mythological characters which are sub deities, for example, the Marvel Comics super heroes, the Hulk, Captain America, etc.
Hollywood movie themes where a parallel universe or illusory world are present.
Television programming such as StarGate which seeks the lost knowledge and wisdom of the "ancients" and utterly deny the revelation of scripture, and even indirectly belittle it, all the while the masses of earth dwellers are ignorantly unaware of the true knowledge of what is going on in the universe.
Perhaps the following portion from Colossians 1 is the safeguard and test, wherever this is denied or downplayed, maybe the seeds of gnostic thought are present. Herein is the nature of man exposed, his need for help outside himself, the presence of that which judges him, and the Savior/Judge who triumphed over all through death & resurrection:
21 And you, that were sometime alienated and enemies in your mind by wicked works, yet now hath he reconciled 22 in the body of his flesh through death, to present you holy and unblameable and unreproveable in his sight:
In Him is all the fullness of knowledge, beware of false so called knowledge.