Thoughts are the play of pure awareness. They arise within it and dissolve back into it. To recognize pure awareness as the very source of thought is to recognize that our thoughts have never begun, continued or ceased to exist. At that point, thoughts can no longer trouble the mind.
As long as we run after our thoughts, we are like a dog chasing a stick. Each time we throw the stick, he runs after it. If we look at the enlightened consciousness instead, the source of our thoughts, we will see that each thought arises and dissolves in the space of that consciousness, without engendering other thoughts. Then we will be like a lion, which does not chase after the stick, but turns to face the thrower. You can throw a stick at a lion only once.
To conquer the uncreated citadel of the nature of mind, we must go to the source and recognize the origin of thoughts.”
Dzogchen Master Jamgon Kontrul Rinpoche