8.
The Discourse on Brahmā
384.
On one occasion the Blessed One was dwelling at Uruvelā on the bank of the river Nerañjarā at the goatherd's banyan tree, newly fully enlightened.
Then, when the Blessed One had gone to a private place and was in seclusion, this reflection arose in his mind:
"This is the one-way path for the purification of beings, for the transcendence of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the true method, for the realisation of Nibbāna, that is to say -
the four establishments of mindfulness."
"Which four? A monk should dwell observing the body in the body, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world; or a monk in feelings, etc. or a monk in mind, etc. or a monk should dwell observing mental phenomena in mental phenomena, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world. This is the one-way path for the purification of beings, for the transcendence of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the true method, for the realisation of Nibbāna, that is to say - the four establishments of mindfulness."
Then Brahmā Sahampati, having known with his mind the reflection in the mind of the Blessed One - just as a strong man might extend his bent arm or bend his extended arm, even so - having vanished from the Brahma world, appeared before the Blessed One. Then Brahmā Sahampati, having arranged his upper robe on one shoulder, having extended joined palms in salutation towards the Blessed One, said this to the Blessed One - "So it is, Blessed One, so it is, Fortunate One! This is the one-way path, venerable sir, for the purification of beings, for the transcendence of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the true method, for the realisation of Nibbāna, that is to say - the four establishments of mindfulness."
"Which four? A monk, venerable sir, should dwell observing the body in the body, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world; or, venerable sir, a monk in feelings, etc. or, venerable sir, a monk in mind, etc. or, venerable sir, a monk should dwell observing mental phenomena in mental phenomena, ardent, fully aware, mindful, having removed covetousness and displeasure regarding the world. This is the one-way path, venerable sir, for the purification of beings, for the transcendence of sorrow and lamentation, for the passing away of pain and displeasure, for the achievement of the true method, for the realisation of Nibbāna, that is to say - the four establishments of mindfulness."
This Brahmā Sahampati said. Having said this, he further said this -
By this path they crossed before, will cross, and those who are crossing the flood." The eighth.