Tentative of definition of Gnosis in Christian Tradition

What could be gnosis and what is its definition? Many historians talked about this question trying to distinguish gnosis of revealed religions - if there are many - and gnosis called pagans.
Behind gnosis there is the problem of God knowledge, and Jean-Pierre Bonnerot raises in this 30-minutes interview many questions: (1) How to know God, and what state do we have to reach to "be born with" divine?  (2) For what reasons did Latin Christianism, from the 2th century with Iréné de Lyon, considered Gnosis as heretic while Saint-Paul wrote just before him:  "there is a superior knowledge to human wisdom towards which men have to aim at". What would be that supra-human wisdom?

(3) Why do we count in eastern church of gnostic monks and not in apostolic roman? (4) From what filiation Constant Chevillon, Jean Bricaud, Victor Blanchard, Robert Amblain, Robert Amadou, Edouard Gestas, René Chambellan claimed to belong to when they tried to establish a gnostic church in France, last century?

To Jean-Pierre Bonnerot, gnosis is a matter of Inner Church. Like original theosophy of the 17th century, it gives a symbolical and coherent explanation of man's place, God and Universe.  It is like an invitation which is suggested to Man to become co-redemptioner of creation, to act so that elements (animals, plants, etc) which have been dragged in its fall, find their original state.
Far from all form of power or "Faustian" pact, the principle of Gnosis is to accomplish this task, by the grace of Holy Spirit... but, according to the author, "what is Gnosis but acquisition of Holy Spirit? "...