"While breathing in long, he fully comprehends 'I breathe in long'. While breathing out long, he fully comprehends 'I breathe out long'.
"While breathing in short, he fully comprehends 'I breathe in short'. While breathing out short, he fully comprehends 'I breathe out short'.
"He trains himself, 'thoroughly experiencing all bodies I shall breathe in'. He trains himself, 'thoroughly experiencing all bodies I shall breathe out'.
"He trains himself, 'Calming the body-conditioner I shall breathe in'. He trains himself, 'Calming the body-conditioner I shall breathe out'.
From the translation found in "Mindfulness with Breathing" by Buddhadasa Bhikkhu.
Buddhadasa talks about the long/short breaths as separate contemplations. One should "regulate" the breath and explore the effects of the long breath, and then the short. How does it affect the body? The mind?
I've found Analayo's explanation to be better suited to me. He explains that the first two lines imply a
progression as one focuses on the breath. It's true. If you watch the length of each breath, noticing if it is shorter or longer than the last AND pay attention to it's effects on the body and mind the breath will naturally shorten and become very fine.
This has led to both an
excess of piti and before that an
excess of tension in my practice as the breath gets extremely fine and the mind very one-pointed.
The way forward I've found (with much help here at the DhO!) is partly to relax into it, (familiarity with an oft repeated experience no doubt plays a part here also), partly to regulate it (don't left it get to fine/one-pointed before I'm ready) and partly to diffuse the attention at the optimal moment in
step 3.
"thoroughly experiencing all bodies" is taken to mean the flesh-body and breath body. One contemplates the effect one has on the other. I've noticed that this happens automatically now, though this was not always the case. As I breathe I can feel a flow of energy through the flesh body that is intimately linked to the breath. I can feel the breath conditioning the body. It's like both bodies become one. If I focus I can also see different "strands" of energy. One of those strands is clearly the as yet immature feeling of piti --this has led me to believe that piti is actually always there. I'm not creating piti when I enter jhana, I'm
noticing it. It's the sustained one-pionted attention on it that makes it "arise".
'Calming the body-conditioner I shall breathe in' in my best interpretation is linked/merged/one with steps 5 and 6 of experiencing piti and sukkha. As the breath is calmed by a mixture of anapana spot, body awareness/linking and finer and finer mindfulness it slowly creates the jhanas. Not the jhanas Buddhadasa talks about (commentarial jhanas) but the softer jhanas one can think in. Known here on DhO as sutta jhanas I believe.
I'll talk about those when I make some notes n the 2nd tetrad.
More learned and differing opinions much appreciated...