At Sāvatthī. “Mendicants, when the perception of a skeleton is developed and cultivated it’s very fruitful and beneficial. How so? It’s when a mendicant develops the perception of a skeleton together with the awakening factors of mindfulness, investigation of principles, energy, rapture, tranquility, immersion, and equanimity, which rely on seclusion, fading away, and cessation, and ripen as letting go. That’s how the perception of a skeleton, when developed and cultivated, is very fruitful and beneficial.”