There’s a time when a mendicant practices like this: ‘I’ll breathe in experiencing rapture … bliss … mind …’ … They practice like this: ‘I’ll breathe in stilling the mental process.’ They practice like this: ‘I’ll breathe out stilling the mental process.’ At such a time a mendicant is meditating by observing an aspect of feelings—keen, aware, and mindful, rid of covetousness and displeasure for the world. Why is that? Because careful application of mind to the in-breaths and out-breaths is a certain aspect of feelings, I say. Therefore, at such a time a mendicant is meditating by observing an aspect of feelings—keen, aware, and mindful, rid of covetousness and displeasure for the world.

There’s a time when a mendicant practices like this: ‘I’ll breathe in experiencing the mind.’ They practice like this: ‘I’ll breathe out experiencing the mind.’ They practice like this: ‘I’ll breathe in gladdening the mind … immersing the mind in samādhi … freeing the mind.’ They practice like this: ‘I’ll breathe out freeing the mind.’ At such a time a mendicant is meditating by observing an aspect of the mind—keen, aware, and mindful, rid of covetousness and displeasure for the world. Why is that? Because there is no development of immersion due to mindfulness of breathing for someone who is unmindful and lacks awareness, I say. Therefore, at such a time a mendicant is meditating by observing an aspect of the mind—keen, aware, and mindful, rid of covetousness and displeasure for the world.

There’s a time when a mendicant practices like this: ‘I’ll breathe in observing impermanence … fading away … cessation … 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.

That’s how immersion due to mindfulness of breathing is developed and cultivated so as to fulfill the four kinds of mindfulness meditation.