Even as a relative beginner, you get to know about moon days pretty early on.
The idea of taking a day off or two of practice each month seems pretty appealing, pretty quickly. in accord with the full and the ‘dark’ moon this was first started by Pattabhi Jois, as a rest day in order, apparently, to avoid the more unstable energy around these occurrences. There is no particular injunction in the scriptures I have ever read of to refrain from practice at these times. Some older students, instead, suggest that it was an extra couple of days off a month that Jois was asked to take by his wife for the sake of family time.
On the other hand, there has always been acknowledgment of the moon as a powerful factor. It has always been said that Emergency Services record definite higher incident rates at these times. Furthermore, it makes sense that the moon exerting such a force on the tides of the sea, would also do so on our own body, roughly 60% water itself. Just as with the tides; it is supposed that it influences the body-energy through its’ water composition, to the extremes of a high-tide/energy on the full moon, and a low one with the ‘dark’ moon.
I am ambivalent to all of this in my personal viewpoint. I must confess I have never rested over moon days, feeling that there is enough that influences our body energy these days much more strongly and detrimentally than the pull of the moon. Just consider the phones on our person and their associated networks. So, it has always been my thinking that the body is not truly so aligned these days that this influence would really be felt; yet, it has often been the case that when a little tweak or some-such small complaint happens, that is on these days. In which case, I am also at pains not to discredit this possibility either.
However, it is still my opinion that just as it is essential to use the body every day, moon days included, why can we not also use the body in conscious activity? Of course, if the nature of practice is defined by pushing oneself to the degree that a rest is essential, then that is a matter that might warrant reflection. Whilst, if the practice is more thoughtfully applied I can see no reason why it cannot be carried on everyday.
Which means, indeed, that some days, not necessarily moon days, practice may be less energetic in an acknowledgement of how we feel. It is hoped that a categorical day is not needed in order to be able to recognize this. Still, if this ability to allow for our essential variability, and apply a sense of reflection and compassion to practice is not forthcoming without a designated day, then, so be it. Use the day as long as it is needed.
But, then do not cling on to it. For at some point, practice has to become a vehicle for owning up to the frightening proposition that it is only us that can, and therefore must, take responsibility for our own lives and practice.
Within any method, especially one with so many rules and politics as ashtanga yoga, it’s all too tempting to absolve oneself of this task, by hiding behind what are, in the end, only someone else’s suggestions, however nicely laid out.
Yoga, I feel, is a pragmatic attempt at living life skillfully; so as to be effective where one can, and cause as little suffering and harm to others as is possible. To that ends, knowing change and variation to be the only constant in the substratum of life, it seems in error to conceptualise an overly rigid framework around it. In which case, it’s hardly a sin to practice over these days; especially if you happen to have missed other days over the month.
Furthermore, as a final thought (indeed, a constant refrain with me), if practice is about pushing oneself against natural boundaries, then it will result in injuries regardless of whether moon days are taken off. In contrast, if it is about working in awareness, surely all days can be used to do this; ones in which the energy is a little more yang, as well as those more yin. Within this line of inquiry, there appears no need to completely refrain from the daily task of focus and mind-training. It would be a shame if the practice was conceived in such a physically forceful way that it demanded this kind of a break from itself.