Peace is the Essence
During meditation we are able to experience a deep peace: it may be in our body, mind, emotions or heart.
Regardless of where we experience the sensation it is this very peace that is the seed of the universe. Just as a river flows through many different lands and terrains so to does that seed of peace flow and animate many parts of our being.
By feeling and focusing on that peace you can trace it back to the Source. That conscious experience is illumination.