The way I understand this is through http://en.wikipedia.org/wiki/Theory_of_Forms.

The theory of forms is an old and completely discredited derivation of an ancient sophistry that nevertheless had its ripples felt in every corner of Western philosophy.

It is related to Gnosticism, because it is basically the foundation upon which Gnosticism had to be built, but it is older than Gnosticism itself.

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To start with, we have to look at one of the most ancient of philosophical [http://en.wikipedia.org/wiki/Heracletus]statements[/url] that still remains with us - that the universe changes. This isn't much of a statement, I know, but all things have to start small. The statement of this idea was that nothing in the world was eternal, that everything was in flux.

The metaphor was that of a river - the river may appear to be the same river in the same place, but in actuality, the river is nothing more than a collection of water drops, and those water drops are moving away from you. If you were to walk into the river today, it would not be the river you would have stood in yesterday, for the water in it yesterday has all long since gone by, and "river" is just a name we give for a pattern of water because we cannot perceive the every drop of water.

By extension, the you of today is not the you of yesterday, much less the you of 10 years ago. In that time, you have changed. You have changed for in ten years, you have eaten, you have drunk, you have bleed, you have grown, but these are only the physical things, you have also learned and you have grown as a mind. The You you are now will not be in the future. You will forget. The pride and pain of the now-you will be gone, lost to the will-be-you who cannot recall. Then, you will die.

It was the furthest extension of this that most terrified people, however, for it claimed that existence was subjective. That is, because we are trapped in the prison of our own minds and our own mindset, capable of seeing only the shadows of the world through the peep-holes of our five senses, and the play-acting of our own imagination, internal dialogue of reason, and memory, our world is warped both through the deficiencies of our senses, the shortcomings of our imagination, the fallacies of our logic, but worst of all, the fading and the distortion of our memory. Everything we are and everything we sense will be lost to us through the ravages of time.

This is the philosophy of Change.

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Against this, then, rose the great sophistry by those who rejected this horrifying realization. They made their case through metaphor, as well. It is called "http://en.wikipedia.org/wiki/Zeno%27s_paradoxes", and it goes like this:
Achilles is in a race with a tortoise. Achilles is, of course, a most athletic man, and can easily outrun a tortoise, but the tortoise has a head-start, being several meters ahead of Achilles at the start of this race. As such, Achilles must run to catch up to where the tortoise is. However, when Achilles gets there, the tortoise will have moved. So, Achilles must run some more to reach the point where the tortoise now is. However, when he gets there, the tortoise has moved some more. This repeats forever, and therefore, no change has actually taken place - the tortoise will forever be in the lead.

This was, for some reason, impossible for ancient philosophers to properly refute, causing them to believe it.

This claim was that there was no time because there was no change.

I will refute it now:
In that metaphor, what was actually happening is something you could graph out with basic algebra - draw two lines on an X/Y graph of different slopes, and somewhere down the line, they will intersect. In order to achieve the sophistry they achieved, however, they talked about how each interval of reaching the point where the tortoise is now would require time, but by the time that Achilles got there, the tortoise would have moved. However, this interval of time would grow shorter, because movement is distance over time. The period of time between when Achilles would finally overtake the tortoise, then, would be growing infinitely shorter until it infinitely approached the limit of zero.

In other words, they were claiming that there was no time because there was no change if we assume there is no time.

To shorten this even further, the claim is: "If there is no time, then there is no time."

This is a tautological, and hence meaningless claim.

However, this claim that time was a falsehood was used as a way to try to destroy all of the other claims of the philosophy of change.

To quote Wikipedia on this, http://en.wikipedia.org/wiki/Parmenides divided up reality into two things based upon this "time does not exist" idea:
In "the way of truth" (a part of the poem), he explains how reality (coined as "what-is") is one, change is impossible, and existence is timeless, uniform, necessary, and unchanging. In "the way of opinion," he explains the world of appearances, in which one's sensory faculties lead to conceptions which are false and deceitful.

Or, in other words, there is a perfect theoretical world without time, and then there is the corruption of that perfect that exists only because you have senses and a perception of time's existence.

On top of this was added the theory of "recollection", that we, in fact, do not learn. We are born with all knowledge, we just don't remember having it. Learning is, in fact, just remembering something we always knew, because we could not perceive we always knew it because of that awful corrupting time perception.

Because it started from a false assumption, however, everything from this school of thought is total bunk, and cannot possibly be, at least, as long as Time exists, as the entirety of the philosophy is predicated upon time not existing.

Because it can only exist as long as there is no time, it is the philosophy of Stasis.

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Plato, then, came about to try to weave these two diametric opposites into a synthesis. This synthesis would, of course, http://www.othieves.com/art_plato.html, because Zeno's Paradoxes were founded upon a fallacy, but nevertheless, Plato became the bedrock of Western Philosophy because between him and Aristotle (who basically was a student of his work), he introduced not just the notion of souls and the split between mortal and divine that Christianity adopted, but basically was declared THE way in which the world worked by the Roman Catholic church in such a way that it was responsible for stunting philosophical and scientific discovery until the time of the Protestant Reformation and Galileo completely broke science off from philosophy.

His synthesis went like this:
There was such a thing called the "http://en.wikipedia.org/wiki/Theory_of_forms". This was done through the http://www.youtube.com/watch?v=d2afuTvUzBQ.

Basically, he claimed that there was change, and there was a physical world, and there was time, but that they were all "corruptions" of the true Forms.

Forms are the perfect, eternal archetypes upon which all physical reality was created as mere corrupt distortions of the shadows of the true Forms. So all chairs, for example, are derived from the One Perfect Chair. All varieties of chairs are just different corruptions of the One Perfect Chair's perfect chairness. Physical chairs are bound by time and break because they are corrupt, but the One Perfect Chair is eternal and unchanging.

Again, Plato held up the Theory of Recollection - we have a perfect, eternal soul, but that is corrupted by our physicalness and having a body and having wants and desires and emotions and pleasure and individualism and freedom.

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So, then, we come to Gnosticism.

Gnostics believed that they were once a part of an eternal perfect realm of immortal souls that existed without physicality or time. Then, a jealous under-god of the True God called The Demiurge created physical reality behind the True God's back. However, the Demiurge was imperfect, and what the Demiurge created was corrupted by imperfection, and so too were the perfect immortal souls that were caught up in the Demiurge's creation.

Physical reality, then, is a prison to Gnostics, and all life and all physical reality is made of pure corruption upon their perfect eternal selves. The overarching goal of Gnosticism is to abandon all flesh and live entirely for re-connecting with this perfect eternal divine through the act of denial of the flesh. (It's worth pointing out that they were entirely against having children, because life is the corruption of a living being's soul, and therefore, creating life was evil. They were also against having six or having fun in any way through physical means, because those were all corruptions of your own soul, as well. Needless to say, they weren't quite capable of "spreading the word" fast enough to replace their own mortality rate, and would have died out even if the early Christians hadn't thought they were heretics and had them all rounded up. With that said, Gnosticism had an unmistakable impact upon Christianity, along with Sassanid Zoroastrianism's dualism of cosmic Good and Evil.)