[643] Setting at Sāvatthī. Bhikkhus, the perception of a skeleton (aṭṭhikasaññā), when developed and cultivated, leads to great benefit. And how, bhikkhus, is the perception of a skeleton developed, how is it cultivated, so that it leads to great benefit? Here, bhikkhus, a bhikkhu develops the mindfulness factor of awakening (bojjhaṅga) accompanied by the perception of a skeleton … he develops the equanimity factor of awakening accompanied by the perception of a skeleton — based upon seclusion, based upon dispassion, based upon cessation, maturing in relinquishment. It is when the perception of a skeleton is developed thus, bhikkhus, cultivated thus, that it leads to great benefit.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.