Eka tattva abhyasah means to cultivate one-pointedness of mind.
The circles appear to move, but are actually stationary. Focus on any of the small black circles (in the center) and the motion stops!
Meditation is similar to this picture. Meditation in action is also similar.
Train the mind to be one-pointed and the inner obstacles come to rest!
Excerpt From swamij.com Article Yoga Sutras 1.30-1.32: Obstacles and Solutions