See it, Think it, ... Say it! “Don’t be your thoughts, be the awareness of them” encapsulates the sentiment of the “Illusionary Self”, and "Egoic Mind" discussed and elaborated upon in Eckhart Tolle's book, A New Earth: Create a Better Life.
All quotes on this page further explaining the Illusionary Self / Egoic Mind are taken directly from the 10th Anniversary Edition of A New Earth: Create a Better Life, published in 2016 by Penguin Books Ltd, unless otherwise attributed. Any commentaries associated with the quotes are mine alone, and may or may not reflect Eckhart Tolle’s actual intent.
In normal everyday usage, “I” embodies the primordial error, a misperception of who you are, an illusory sense of identity. This is the ego. (p. 27)
That illusory self then becomes the basis for all further interpretations, or rather misinterpretations of reality, all thought processes, interactions, and relationships. Your reality becomes a reflection of the original illusion. (p. 28)
What you usually refer to when you say "I" is not who you are. By a monstrous act of reductionism, the infinite depth of who you are is confused with [the word] or the thought of "I" in your mind and whatever the "I" has identified with. (p. 28)
When a young child learns that a sequence of sounds produced by the parents ... is his or her name, the child begins to equate a word, which in the mind becomes a thought, with who he or she is. ... Soon after, they learn the magic word "I" and equate it with their name ... then other thoughts come and merge with the original I-thought. The next step are thoughts of me and mine to designate things that are somehow part of "I". This identification with objects ... becomes part of the child's developing sense of self, of "I". (pp. 28-29)
And so as the child grows up, the original I-thought attracts other thoughts to itself: It becomes identified with a gender, possessions, the sense-perceived body, a nationality, race, religion, profession. Other things the "I" identifies with are roles — mother, father, husband, wife, and so on — accumulated knowledge or opinions, likes and dislikes, and also things that happened to "me" in the past, the memory of which are thoughts that further define my sense of self as "me and my story". (p. 29)
In most cases, when you say “I”, it is the ego speaking, not you … it consists of thought and emotion, of a bundle of memories you identify with as “me and my story", of habitual roles you play without knowing it, of collective identifications such as nationality, religion, race, social class, or political allegiance. (p. 60)
As long as you are completely unaware of this, you take the thinker to be who you are. This is the egoic mind. We call it egoic because there is a sense of self, of I (ego), in every thought – every memory, every interpretation, opinion, viewpoint, reaction, emotion. This is unconsciousness, … the content of your mind, [which] is of course conditioned by the past: your upbringing, culture, family background, and so on. (p. 59)
Eckhart's illusory self / egoic mind has a number of parallels with that which Buddhism refers to as a conditioned mind. A conditioned mind does not see reality, but rather, creates an imagined world strongly influenced by historical conditioning. I.e. Through interaction with others — our parents, our schooling, the media, and our culture, etc. Without awareness, we often believe, and accept, this imagined world as the real world.
"A conditioned mind is not aware of its conditioning. It does not see its own conditioned mind that runs on autopilot, preconceived ideas and beliefs. It is a sleeping mind. It is not fully awake." (Dr. Ong Tien Kwan, "The Conditioned Mind".)
Any conceptual sense of self — seeing myself as this or that — is ego, whether predomininately positive (I am the greatest) or negative (I am no good). (p. 86)