In the 1st century ACE, a group of Christians known as Gnostics promoted their own take on Jesus Christ and the search for 'God'. Their particular heretical beliefs were that the Christ was not of divine origin, and that he was in fact a teacher facilitating a process whereby individuals found 'God' within.
It's perhaps the closest that Western civilisation ever came to having a more 'Eastern' view of religion - that is, finding the divine spark within through a system of self-exploration. As Elaine Pagels writes in the introduction to her book THE GNOSTIC GOSPELS:
The first essential characteristic of Gnosticism was introduced above: Gnosticism asserts that "direct, personal and absolute knowledge of the authentic truths of existence is accessible to human beings," and that the attainment of such knowledge is the supreme achievement of human life. Gnosis, remember, is not a rational, propositional, logical understanding, but a knowing acquired by experience. The Gnostics were not much interested in dogma or coherent, rational theology--a fact which makes the study of Gnosticism particularly difficult for individuals with "bookkeeper mentalities".
I found this quote quite ironic. As most now know, by the time of Constantine the definition of Christianity, and the establishment of rituals and rules for the creed, had become quite rigid and have stayed that way for a millenium and a half. The only thing to have swayed the power of Christianity (in the Western world) since that time has been the Enlightenment, the 'Age of Reason' - the scientific revolution. Since that time, many would argue that science has come to be the dominant (or at least, orthodox) thought form, dictating how we are supposed to think.
So this attempt at personal union with the divine, originally squashed by the church, is now - despite the rise of a new paradigm - still heterodox. Those not in line with the religious thought of the church are pagans, heretics, or in league with Satan, and often treated as misguided souls. Those who believe in more than syllogistic thinking, the cold scientism which ignores the richness of life, are 'alternative thinkers' or worse, nutters (or in the taunting vocabulary of that paragon of materialism, James Randi - 'woo-woos'). Beyond that, those who consider the use of entheogenic plants as a method of self-exploration are considered criminals.
Why have we run scared from this idea for the past two millenia? Is it the collective fear of society, that if people think individually that our civilisation will collapse? Is it the controlling heirarch, controlling thought to ensure that nobody rocks the boat? Or are we just scared of dipping beneath our superficial shells and seeing what lies beneath?