Today we completed our 5 day sesshin and it is Hosan tomorrow (no scheduled zazen). So this little guy will be keeping my zafu warm for me. His/her posture needs a little correction I think. It looks a little like my posture in the afternoons when I was trying to avoid the pain spreading across my back. An upright posture is fundamental to zazen (we sit with the body, not with the mind) but there were quite a few times during the sesshin when I drooped.
Pain or, more particularly, fear of pain was the biggest issue for me, and I'm guessing for many of us who have not sat a sesshin of this length before. People can also experience boredom, sleepiness, anxiety, hunger, nausea... what else? General overwhelming distress (I certainly did!), anger, itchiness, being too cold, too hot. So why would any sane person engage with this practice? Well there were pleasant things too: birdsong, frogs, sunlight, sound of rain, a different sense of time... but learning to accommodate things I normally avoid is an important part of this practice, and seeing my reactions to these things. (Why? Maybe I'll explain another time.) So, anyway, while I experienced more pain than I have before during zazen, there was plenty of time to observe how it moves, changes and responds to fear.
Toward the end of the sesshin the fear decreased and the pain became less of a problem (that was the general pattern anyway). Perhaps I felt the end was not too far off. Perhaps I was just exhausted. In any case, I found that keeping a straight posture (instead of cringeing) was the best way to accommodate the pain, as well as other challenges - impatience for the sound of the kaishaku before mealtimes, for instance.
Today is Kodomo no Hi (children's day in Japan). Outside my window last week the carp kites were flying in preparation - although today they probably got a little wet and droopy.