[The following was from IntegralChristian.org, which is no longer an active link]:
The state of awareness that we are practicing when we mediate is called the witnessing state or the witness. In a typical meditation practice, we sit still and focus our awareness on a single object, such as counting our breath or repeating a mantra. As soon as we become aware that our mind has wandered off in thought, we just notice that, and return our awareness to our focus object. When we do this, we are practicing being in witnessing awareness. In other words, we are practicing being the witnessing part of our mind watching the thinking part of our mind repeatedly get carried away in thought.
Remember we learned that “subject” is something I identify as me, and “object” is something I identify as not me.
“Subject” is what’s on the inside of my face looking out, and “object” is everything on the outside of my face that my subjective self is looking at.
In our average everyday waking state of consciousness, we experience our individual self – our body, thinking mind, and feelings – as subject. And we experience everyone and everything outside of our individual body and mind as objects.
When we meditate, we are practicing a shift in our awareness. We are practicing being the witness “watching” temporary thoughts come and go in our minds, and temporary feelings and sensations come and go in our bodies. In other words, we are temporarily making our entire individual self – our entire body and thinking mind – into an object in a larger witnessing awareness. When we do this, we are temporarily shifting our subjective sense of self – our identity – from our gross body and thinking mind to the Witness.
When we aren’t doing something like meditating – when we’re back in our everyday waking state of consciousness – it isn’t that the Witness is somehow gone. Witnessing awareness is always present, but since we identify only with the thinking part of our mind as our “self,” we don’t usually notice that the Witness is there, or experience it as our “self.”