Aṅguttara Nikāya,
Catukkanipātapāḷi
Pañcamapaṇṇāsakaṃ
Rāgapeyyālaṃ
Satipaṭṭhānasuttaṃ
'For passion, almsmen, for getting acquainted with, four principles should be cultivated.
Which four?
Here, almsmen, an almsman looking into body dwells in body as the ardent aware meditator would be disciplining the avarice plus distress about the world.
Looking into feelings dwells in feelings as the ardent aware meditator would be disciplining the avarice plus distress about the world.
Looking into mind dwells in mind as the ardent aware meditator would be disciplining the avarice plus distress about the world.
Looking into principles dwells in principles as the ardent aware meditator would be disciplining the avarice plus distress about the world.
For passion, almsmen, for getting acquainted with, these four principles should be cultivated.'