Saṃyutta Nikāya 47
Connected Discourses on the Establishments of Mindfulness
“Bhikkhus, those for whom you have compassion and who think you should be heeded—whether friends or colleagues, relatives or kinsmen—these you should exhort, settle, and establish in the development of the four establishments of mindfulness.
“What four? Here, bhikkhu, a bhikkhu dwells contemplating the body in the body … feelings in feelings … mind in mind … phenomena in phenomena, ardent, clearly comprehending, mindful, having removed covetousness and displeasure in regard to the world.