Then Venerable Mahāmoggallāna knew what Venerable Anuruddha was thinking. As easily as a strong person would extend or contract their arm, he reappeared in front of Anuruddha and said to him:

“Reverend Anuruddha, how do you define the undertaking of the four kinds of mindfulness meditation by a mendicant?”

“Reverend, it’s when a mendicant meditates by observing an aspect of the body internally—keen, aware, and mindful, rid of covetousness and displeasure for the world. They meditate observing an aspect of the body externally … internally and externally—keen, aware, and mindful, rid of covetousness and displeasure for the world.

They meditate observing an aspect of feelings internally … externally … internally and externally …

They meditate observing an aspect of the mind internally … externally … internally and externally …