The key to sitting Zazen is a dynamic spine. In turn, the key to that is the correct positioning of the pelvis so our physical weight is dropping down through our sit bones and our energetic weight, as it were, is dropping down through our base chakra.
If we’re sitting in the correct position, certain consequences follow. For example, when we breathe in, there’s a subtle and natural push down on the base chakra. It’s as if the base chakra pushes the earth and the breath floods in through there upwards, up through the body to the top of the head, and slightly beyond. It’s like a wave coming in, followed by a naturally slower out breath, like a receding wave, falling naturally downwards through the body.
On the outbreath, alongside the downward movement, there’s a subtle and natural downward pressure. And we might think, “well, a little downward pressure is a good thing so more downward pressure must be a better thing”. And so we might consciously push down with our diaphragm, or consciously compress or otherwise act on our stomach muscles.
Similarly if our spine is dynamic, our head is naturally going up, the back of our neck is stretched and our chin is slightly tucked in, naturally. Yet we might think it a good idea to stretch the back of the neck more. So we tense our muscles and tuck our chin in more.
This is the behaviour of an idiot.
What we require to do once we put our body in the correct posture is just to trust entirely in Zazen. If we do, all the nonsense of our self arises within Zazen. If we attempt these ‘helpful’ interventions, Zazen is arising within the ego, like everything else.
And it’s no good.