Gnostics believe in God; most often the Abrahamic (Christian, Jewish, Muslim) God, but not always. In a Gnostic's case though, He is a divine and supreme being that is UNknowable. He/She/It is a remote presence that is at turns, good, evil, indifferent, loving---as the concept of God embodies everything. Though God has these qualities, She is still seen an benevolent.
At the core of Gnosticism is thought. Gnostics believe that knowledge and spiritual study and meditation are the ways to understand the world and God. They combine logic and rationality with spirituality and faith. Many times, people combine being Gnostic with another faith; AKA a Christian Gnostic.
Gnosticism is dead. It died when Muslims invaded Egypt.
The Nag Hammadi books found are the works of the Gnostics. Where you hear the lost books of the Bible, most of them are Gnostics. There beliefs wouldn't hold water in our day. They don't believe in the resurrection and don't believe Jesus died on the Cross for our sins. They mingle Hellenistic neoplasm philosophy and sprinkle it with Christianity.
It is really a philosophic organization that believes that the body is evil and the only way to salvation is to learn the gnostic writings.
I think if you look at all the major movements in religious thought, they tend to be like pendulum swings. Whenever the mainstream goes too far in one direction, a new movement crops up to steer things back the other way. I think the fact that gnosticism - which is really the original Christian heresy (in a historical sense; don't take offense to the term please) - is gaining momentum at this point in history is very significant. Too much of the Church has slipped into the "idolatry of text" to use a Jewish rabbi's term. They've substituted a finite text for an infinite God. Gnosticism at its core is about experiencing the infinite living Word of Christ, not the static finite words of the printed page.
It is a mainstream approach. Much more so than what is taught as Christianity today. Check out "The Gnostic Society" on the web, it has all the Gnostic Gospels and much more, and if they still have it there is a very, very good talk on The Story of the Pearl, well worth the listen.
I hope it doesn't become mainstream, in fact I don't think it is possible unless it is taken out of context to appease or fit the needs and understanding of the multitude, but this has happened to everything, which is why Gnosticism in regards to Christianity was its higher level but was snuffed out, so to speak.
Basically when it comes to Gnosticism, there were many sects. Some sects were not "Christian," some had more to do with with Seth (Adam's son) and they were called Sethians, there were more then this, but a common thread among them were that 1) they all were seeking nosies, which is Greek for Knowledge, but not linear knowledge but knowledge which is more so direct experience or direct acquaintance in knowing/becoming. To them this was the means by which salvation comes about, i.e. Know thy self - this has absolutely NOTHING to do with reading scriptures. 2) in their Mythology which was just an allegory that the Old testament God was known as Yaltaoboath, or Samael which means false god, and it is actually him which is the main nemesis. It was held that this "god" bound man to physical existence, like in a tomb/prison in order to capture the light which is in them which light is from above, or from their higher spark and etc. 3) They mostly held that scriptures were allegorical for esoteric truths that related to our being in body, mind, and spirit; but since we are holographic it can be metaphoric for forces/laws that occur and not just laws/forces within us (i.e. their beliefs on the first father or the allegoric demure). 4) Most held unto reincarnation/transmigration of souls. 5) the ultimate objective was to know the First Father, the First Cause of everything, to be born into that knowing. Yes they called this First Father, the unknowable, inconceivable one because it is impossible to know until you become as it is, you must become perfect/complete in order to know that source, but some felt it was impossible to know this aspect of God.
They believed in the oneness that people talk about, but they called it the fullness of varying degrees, we would be the fullness within the mind of God/or Logos, although. Jesus/Yeshua was seen as a reveal er, one who shows the way out of this quagmire and provides through his image the potential of what we can all become if we come to know our true selves, as well as revealing what we are up against. They believed he came knowing and was able to manifest the indwelling Logos within himself. And No they didn't reject the resurrection, however they applied it in the right manner and knew that the resurrection was something that you achieved while you were ALIVE, the reconstitution of your form into its original state, or source (Know thy self).
The biggest Gnostic teacher ever was Valentinus (they term his teachings Valentinian thought), he was a mystic/spiritual Christian. This is how different the church was back then, at one point he was in the running of becoming the bishop in Rome, but loss by a very small margin. Was well respected and quite influential. But later authorities as the doctrine declined within the church dubbed him a heretic, just like they did great early Church Fathers Clement and Origen. Also after the Nicea meeting, in the 4th century what can only be described as pure genocide was enforced on Gnostics (Ebionites etc) and they all ended up getting killed, most of their scriptures being destroyed, and etc. The Nag Hammadi was more than likely hidden at this time, because they knew what was coming by way of the Emperor and his need to make Orthodoxy and edited scriptures the authority as a system of control. But good thing these guys hide so many of their scriptures for future generations to find them, you can kill the body, but the idea will remain in some shape or form preserved to some capacity.
Not sure if they were into meditation as much as the eastern schools of thought were, however what was BIG for them was the bridal chamber because of the marriage of male/female becoming one flesh. This concept of male/female becoming one, so they are neither male nor female was so important, but yet view understand what it was referring to. Actually the teachings on male and female were directly taught in the scriptures but they were removed, but the scriptures themselves have this concept interwoven into every PART of the story. Basically were most make the male/female one flesh on all levels of our being.
I believe the re-emergence of some interest in Gnosticism came via the discovery of the Judas Gospel and the Da Vinci code movie (which was complete fantasy). If people do research they will see how Gnosticism was the core of what it all was about.
I could've gave a link which would've been better, but I thought I would put in the effort to say a few things from my own understanding. Been a Gnostic my whole life, but realized it when I was 22, might not seem long since I'm only 24.
Is Gnosticism becoming a mainstream approach to Spirituality?
