[402] "Contemplates": how does one contemplate that body? … Thus one contemplates that body.
"Development" (bhāvanā): there are four kinds of development … development in the sense of repeated practice (āsevana). For one who understands the one-pointedness of mind (citta) and non-distraction by way of short in-breaths and out-breaths, feelings (vedanā) arise and are known … Understanding the one-pointedness of mind and non-distraction by way of short in-breaths and out-breaths, he brings the faculties (indriya) together … Therefore it is said: "and he penetrates the meaning of calm."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.