The first principle of Yin Yoga is – every time you come into a pose, go only to the point where you feel a significant resistance in the body. This advice applies to all styles of yoga – yin or yang. Don’t try to go as deep as you possibly can right away. Give your body a chance to open up and invite you to go deeper. After thirty seconds or a minute or so, usually the body releases and greater depth is possible. But not always. Listen to the body and respect its requests.
Consider your will and your body as two dancers. When you watch two dancers in a wonderful performance, they move in total unison. You cannot tell who is leading and who is following. The dance flows with an ease and grace that seems impossible given the effort that must be there somewhere; and yet it is effortless. Too many beginning (and, unfortunately, even experienced) yoga students make their yoga into a wrestling match – the mind contending with the body, trying to force it into postures that the body is resisting. Yoga is a dance, not a wrestling match.
The essence of yin is yielding. Yang is about changing the world; yin accepts the world for the way it is. Neither is better than the other. There are indeed times when it is appropriate and even necessary to change the world. As we have already observed, yang is a quality much admired and modeled in our culture. We are taught at an early age to make something of ourselves, to change the world and leave our mark on it. And that is perfectly normal some of the time. However, we are rarely taught how to balance this quality with the quality of acceptance. We are not given the chance to learn how to not struggle and just allow things to unfold. Part of the yin practice is learning this yielding.
This philosophy is reflected well in a prayer, which has uncertain roots.  It has been circulating the world for perhaps one hundred years. It speaks to this very challenge of balancing yin and yang. The prayer is:
God grant me the serenity to accept the things I cannot change
Grant me the courage to change the things I can change
And grant me the wisdom to know the difference.
Accepting the things we cannot change is the serenity of yin. The courage to change what needs to be changed is yang. Harmony or balance in life comes from having the wisdom to know the difference. This wisdom cannot be given to you or taught to you. It must be earned and learned through your own experience. Our first tattva is the opportunity to gain this wisdom. Listen to your body, go to your first edge and when, and if, the body opens and invites you in deeper, then accept the invitation and go to the next edge. Once at this new edge, again pause and wait for the next opening.
In this manner we play our edges, each time awaiting a new invitation. We ride the edges with a gentle flowing breath, like a surfer riding the waves of the ocean. The surfer doesn’t fight against the ocean, she goes with it. Fighting the ocean is a silly thing to do.
When you come into the pose, drop your expectations of how you should look or be in the pose. There is a destructive myth buried deep inside the Western yoga practice. This myth is that we should achieve a model shape in each pose. That is – we should look like some model on the cover of a yoga magazine. To this end we use our body to force ourselves into a required shape. To dislodge this myth we should adopt the following mantra:
We don’t use our body to get into a pose; we use the pose to get into our body.
Once we have reached an edge, pause; go inside and notice how this feels. You know the pose is doing its work if you can feel the body being stretched, squeezed, or twisted. Those are the three things we can do to ourselves in a pose: we are compressing tissues, stretching tissues, or twisting (shearing) tissues.
Another mantra to adopt in our practice is:
If you are feeling it, you are doing it.
You do not need to go any further if you are already feeling a significant stretch, compression, or twist in the body. Going further is a sign of ego; it is not doing yoga. Staying where you are is embracing yin.
This is not an excuse to stay back and not go deep into the posture. When we play our edges we come to the point of significant resistance. This will entail some discomfort. Yin Yoga is not meant to be comfortable; Yin Yoga will take you well outside your comfort zone. Much of the benefit of the practice will come from staying in this zone of discomfort, despite the mind’s urgent pleas to leave, to move, to do anything but stay. This too is part of the practice.
As long as we are not experiencing pain, we remain. Pain is always a one-way ticket out of the pose. Pain is a signal that we are tearing the body, or close to tearing the body.  Burning sensations, deep twisting or sharp electrical-like pains are definite no-nos – come out immediately. Dull, achy sorts of sensations are to be expected, however. But, no teacher can know what you are feeling; be your own guru at these times and develop your wisdom. Come out when you are struggling to stay at this edge. If you feel your muscles tensing, you are struggling!
Be aware that our edges are not only physical ones; we have emotional and mental edges too. You may find that you are unconsciously holding back from going deeper because if you went one millimeter further you would be flooded with painful memories, thoughts, or feelings. You may not be ready for these yet. Honor your edges wherever they appear. Honor them, but above all notice them!
Playing the edges is not always a “go further go further go further” process. Often we go forward pause go pause maybe back up a little wait then go again or maybe just stop there. Our edges are always changing: yesterday they may have been quite different than today. Our bodies change. Some days we retain more water in our tissues than other days.  Water retention affects our flexibility. We cannot expect that every day our edges will be in the same place. Accept these changes and just take what is offered.
Acceptance: that is the essence of yin.
- — It has been adopted by the Alcoholics Anonymous and is called the Serenity Prayer. Wikipedia claims that the theologian Reinhold Niebuhr originally wrote it in the 1930s or early 1940s.
- — See section The Physical Body for more on this topic
- — We have an unfortunate saying in the West, “No pain, no gain.” If you translate this saying into the yoga language of Sanskrit, it is rendered, “bullshitihi!”
- — Especially for women whose bodies change so much over their monthly cycles.