[289] "And how, bhikkhus, is mindfulness of breathing (ānāpānasati) developed, how is it made much of, so that it fulfils the four establishments of mindfulness (satipaṭṭhāna)? Bhikkhus, on whatever occasion a bhikkhu, breathing in long, knows clearly, 'I breathe in long,' or breathing out long, knows clearly, 'I breathe out long'; breathing in short, knows clearly, 'I breathe in short,' or breathing out short, knows clearly, 'I breathe out short'; trains thus: 'Experiencing the whole body, I shall breathe in'; trains thus: 'Experiencing the whole body, I shall breathe out'; trains thus: 'Calming the bodily formation, I shall breathe in'; trains thus: 'Calming the bodily formation, I shall breathe out' — on that occasion, bhikkhus, the bhikkhu dwells contemplating the body in the body, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world. Bhikkhus, I say that this — namely, the in-breath and out-breath — is a certain body among bodies. Therefore, bhikkhus, on that occasion the bhikkhu dwells contemplating the body in the body, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world.
Bhikkhus, on whatever occasion a bhikkhu trains thus: 'Experiencing rapture (pīti), I shall breathe in'; trains thus: 'Experiencing rapture, I shall breathe out'; trains thus: 'Experiencing pleasure, I shall breathe in'; trains thus: 'Experiencing pleasure, I shall breathe out'; trains thus: 'Experiencing the mental formation, I shall breathe in'; trains thus: 'Experiencing the mental formation, I shall breathe out'; trains thus: 'Calming the mental formation, I shall breathe in'; trains thus: 'Calming the mental formation, I shall breathe out' — on that occasion, bhikkhus, the bhikkhu dwells contemplating feeling in feelings (vedanā), ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world. Bhikkhus, I say that this — namely, thorough attention to in-breaths and out-breaths — is a certain feeling among feelings. Therefore, bhikkhus, on that occasion the bhikkhu dwells contemplating feeling in feelings, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world.
Bhikkhus, on whatever occasion a bhikkhu trains thus: 'Experiencing the mind (citta), I shall breathe in'; trains thus: 'Experiencing the mind, I shall breathe out'; trains thus: 'Gladdening the mind, I shall breathe in'; trains thus: 'Gladdening the mind, I shall breathe out'; trains thus: 'Concentrating the mind, I shall breathe in'; trains thus: 'Concentrating the mind, I shall breathe out'; trains thus: 'Liberating the mind, I shall breathe in'; trains thus: 'Liberating the mind, I shall breathe out' — on that occasion, bhikkhus, the bhikkhu dwells contemplating the mind in the mind, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world. Bhikkhus, I do not speak of mindfulness of breathing for one of muddled mindfulness, lacking clear comprehension. Therefore, bhikkhus, on that occasion the bhikkhu dwells contemplating the mind in the mind, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world.
Bhikkhus, on whatever occasion a bhikkhu trains thus: 'Contemplating impermanence, I shall breathe in'; trains thus: 'Contemplating impermanence, I shall breathe out'; trains thus: 'Contemplating fading away, I shall breathe in'; trains thus: 'Contemplating fading away, I shall breathe out'; trains thus: 'Contemplating cessation, I shall breathe in'; trains thus: 'Contemplating cessation, I shall breathe out'; trains thus: 'Contemplating relinquishment, I shall breathe in'; trains thus: 'Contemplating relinquishment, I shall breathe out' — on that occasion, bhikkhus, the bhikkhu dwells contemplating dhammas in dhammas, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world. He, having seen with wisdom that abandoning of covetousness and grief, is one who looks on closely with equanimity. Therefore, bhikkhus, on that occasion the bhikkhu dwells contemplating dhammas in dhammas, ardent, clearly comprehending, mindful, having removed covetousness and grief regarding the world.
Thus developed, bhikkhus, thus made much of, mindfulness of breathing fulfils the four establishments of mindfulness."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.