There’s a time when a mendicant practices like this: ‘I’ll breathe in observing impermanence.’ They practice like this: ‘I’ll breathe out observing impermanence.’ They practice like this: ‘I’ll breathe in observing fading away.’ They practice like this: ‘I’ll breathe out observing fading away.’ They practice like this: ‘I’ll breathe in observing cessation.’ They practice like this: ‘I’ll breathe out observing cessation.’ They practice like this: ‘I’ll breathe in observing letting go.’ They practice like this: ‘I’ll breathe out observing letting go.’ At such a time a mendicant is meditating by observing an aspect of principles—keen, aware, and mindful, rid of covetousness and displeasure for the world. Having seen with wisdom the giving up of covetousness and displeasure, they watch closely over with equanimity. Therefore, at such a time a mendicant is meditating by observing an aspect of principles—keen, aware, and mindful, rid of covetousness and displeasure for the world.

Suppose there was a large heap of sand at the crossroads. And a cart or chariot were to come by from the east, west, north, or south and destroy that heap of sand. In the same way, when a mendicant is meditating by observing an aspect of the body, feelings, mind, or principles, they destroy bad, unskillful qualities.”

Linked Discourses 54.11 Chapter Two Icchānaṅgala