6.
The Discourse on the Region
392.
On one occasion the Venerable Sāriputta and the Venerable Mahāmoggallāna and the Venerable Anuruddha were dwelling at Sāketa in the Kaṇḍakī Grove.
Then the Venerable Sāriputta and the Venerable Mahāmoggallāna, in the evening, having emerged from seclusion, approached the Venerable Anuruddha;
having approached, they exchanged friendly greetings with the Venerable Anuruddha.
Having concluded the pleasant and memorable talk, they sat down to one side.
Seated to one side, the Venerable Sāriputta said this to the Venerable Anuruddha -
"'Trainee, trainee', friend Anuruddha, is said.
In what way, friend, is one a trainee?"
"Because of having developed a portion of the four establishments of mindfulness, friend, one is a trainee."
"Which four? Here, friend, a monk dwells observing the body in the body, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world; in feelings... etc. In mind... etc. He dwells observing mental phenomena in mental phenomena, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world. Because of having developed a portion of these four establishments of mindfulness, friend, one is a trainee." The sixth.