Could you define the Gnosis for me in general terms?
इस के लेख़क हैं Óscar Uzcategui

"‘It's good to know that etymologically the word “Gnosis” comes from Greek and it means “knowledge”; however, it is clear that we are not talking about ordinary knowledge. The Gnosis refers to a higher Wisdom that is transcendental for humans. This universal and timeless knowledge, wherefrom the great theological, philosophical, artistic and symbolic similarity of the great civilizations of the past has emerged, bearing testimony that all have drunk from the same original source.’

‘The JANA, YANA, GHANA or GNOSIS is the science of JANO, or the science of ENOICHON or of the soothsayer. The word JINA, wherefrom the term GNOSIS comes, is merely the Spanish form of that word; its real writing derives from Parsee and Arabic, and it is not JINA, but DJIN or DJINN, these forms being used by many authors.’

But, I heard that Gnosis is something like a heretical doctrine that emerged from the bosom of primitive Christianity. Is this true?

You may have read statements like that because there are a few works published by religious institutions which seek to intentionally discredit Gnosis and the Gnostics. But such claims do not have a dialectic base. The Gnosis already existed before the advent of Christianity and of Jesus of Nazareth. However, you should know that, for example: : ‘The Nazarenes were known as Baptists, Sabeans and Christians of Saint John. Their belief was that the Messiah was not the son of God, but simply a prophet who wanted to follow John.’

Origen (one of the fathers of the Christian church), in his Vol. II, page 150, notes that:

: ‘There are some who say of John that he was the anointed (the Christos).’

‘When the metaphysical conceptions of the Gnostics, who saw Jesus as the Logos and the anointed, began to gain ground, the early Christians separated from the Nazarenes, who accused Jesus of distorting the doctrines of John and of changing the baptism in the Jordan for another one‘

((This is taken textually from Codex Nazarenus, II, page 109).