You shall know the truth, and the truth shall set you free.
Know what is in front of your face, and there is nothing that will not be revealed to you.
The path of Gnosis isn't only a straight and narrow one, it is a spiral one as well. The descriptions and insight given to us by the Gnostic Tradition are applicable not just once, there is no mere one-to-one correspondence, but again and again. When you find something that they apply to, don't think you've now 'got' it—that you 'know' exactly what it means.
Gnosis is akin to recognition, and the ideas and descriptions are truly helpful in that they aid us in recognizing, and making sense of, our experiences. But there will always be those who have had an experience, and have used it to propel themselves into a delusion that they think is liberation.
Jung termed it Ego Inflation, and it is akin to Paul's comments that there are those who grow into a position, and those that it just 'puffeth up.' An experience of something beyond the ego, is then hi-jacked by the ego. It is a spiritual short-circuit: instead of taking up the next task on the path to the divine, you plop down on a couch and say, “enough, I'm God already.” For example: you enter the Presence, God fills your heart with love, and 'you' take credit for it, “see how loving I am.” Or you have a flash of Gnosis, things 'click' they make sense in a new way, and immediately the thought comes, “see how clever I am.” Ego Inflation is inevitable, but hopefully short lived. It can even be used as a tool of transformation, helping you pass barriers that seemed insurmountable—as long as your feet land back on the ground afterwards.
The danger is that the feeling of Ego Inflation is pleasurable, and your ego wants to believe it is true—desperately. I have had the misfortune of watching many people that I have cared deeply about, walk down this path instead of the one that leads to liberation. They mistake the attempts of the ego to hi-jack the spiritual experience as being the point of the spiritual experience. If they had Gnostic ideas, they mistake the euphoria of Ego Inflation for the liberation of Gnosis. It can become an addiction of sorts.
One of the things that never fails to strike me is how often someone will come into our Ecclesiastical environment, check to make sure we don't have rigid dogmas—then set about trying to impose their own on everyone. The liberation Gnosis offers has nothing to do with the freedom to be an orthodoxy of one, or to impose one person's delusions on others.
If someone walks in and says that God has been talking to them, the only sane response is, “I'm glad you have noticed. It is probably a good indicator that you are at the beginning of a lot of personal work.”
We must always be mindful of the Lord's admonition to remove the beam from our own eye before we go around doing vision correction surgery—yet that doesn't mean we can't see for ourselves at all. Forcing your notions upon others is a different thing altogether from allowing their notions to be forced upon yourself and others.
By their fruits you shall know them: if their fruits are rotten apples and sour grapes—and especially, if their fruits are empty promises and self-importance—they weren't harvested from the tree of Gnosis.