"The application of mastery is by stages"
Now that we have gone through the first two books, we are getting into the territory of esoteric experience. What do I mean by that? Sometime the words we choose to write and speak cannot convey the true intuitive meaning of a Yogic principal, so the best any writer will have is the use of analogies. This is why we see so many religious texts take on a narrative form. How can you best give the sense of feeling other than to put it into a story?
In Sutra 3.6, the concept we are dealing with is called Sanyama. Sanyama is the result of stillness of the mind combined with mediation. Yoga, is and will always be about finding some sort of balance. We live in a world of dualities and our thoughts whisk us between opposing modalities, in essence, tricking into believing that we are following a linear path. In yoga, the linear path runs straight down the middle, working to balance opposites. Sanyama is the balance between meditation and concentration.
In my experience, everything in the Yoga Sutras is a means to an end. When I first started to meditate, I was fixated on perfection. Trying to get the room at the perfect temperature, trying to keep all the noise out by wearing ear plugs, working on getting my meditation posture in the best alignment and so on. I got to a point that I was so focused on perfection, that my routine was doing more harm than good, so I stopped formal meditation all together. For years, it went on like this until I was bashed over the head by the power of the middle ground.
The irony of Sanyama is that the Yogi is simultaneously concentrating and letting go, which leads to and effortless understanding on how to interact with any object of meditation. It's a tool for universal understanding that is used to dig out our subconscious proclivities called Samskaras. I had to learn to find the perfection in imperfection and found that both are just boundaries we draw in our mind. Did you color in the lines when you were a kid? I never did, so I was called a "scribbler". Looking back, I just realized that I was drawing my own boundaries and not living in the box society puts us in as we grow. Try coloring outside the lines, it will do you some good.