[140] And how, bhikkhus, does a bhikkhu dwell contemplating the mind in the mind (citta)?
Here, bhikkhus, a bhikkhu understands a mind with lust as 'a mind with lust,' or he understands a mind without lust as 'a mind without lust.' He understands a mind with hatred as 'a mind with hatred,' or he understands a mind without hatred as 'a mind without hatred.' He understands a mind with delusion as 'a mind with delusion,' or he understands a mind without delusion as 'a mind without delusion.' He understands a contracted mind as 'a contracted mind,' or he understands a distracted mind as 'a distracted mind.' He understands an exalted mind as 'an exalted mind,' or he understands an unexalted mind as 'an unexalted mind.' He understands a surpassable mind as 'a surpassable mind,' or he understands an unsurpassable mind as 'an unsurpassable mind.' He understands a concentrated mind as 'a concentrated mind,' or he understands an unconcentrated mind as 'an unconcentrated mind.' He understands a liberated mind as 'a liberated mind,' or he understands an unliberated mind as 'an unliberated mind.'
Thus he dwells contemplating the mind in the mind internally, or he dwells contemplating the mind in the mind externally, or he dwells contemplating the mind in the mind both internally and externally. He dwells contemplating the nature of origination in the mind, or he dwells contemplating the nature of vanishing in the mind, or he dwells contemplating the nature of both origination and vanishing in the mind. Or else the mindfulness that 'there is a mind' is established in him, just to the extent necessary for knowledge (ñāṇa) and for continued mindfulness. And he dwells independent, not clinging to anything in the world. Thus indeed, bhikkhus, does a bhikkhu dwell contemplating the mind in the mind.
The Establishment of Mindfulness (satipaṭṭhāna) consisting in Contemplation of the Mind.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.