They closely watch over that mind immersed in samādhi. At such a time, a mendicant has activated the awakening factor of equanimity; they develop it and perfect it.

Whenever a mendicant meditates by observing an aspect of feelings … mind … principles, their mindfulness is established and lucid. At such a time, a mendicant has activated the awakening factor of mindfulness; they develop it and perfect it. … (Tell in full as for the first kind of mindfulness meditation.)

They closely watch over that mind immersed in samādhi. At such a time, a mendicant has activated the awakening factor of equanimity; they develop it and perfect it. That’s how the four kinds of mindfulness meditation are developed and cultivated so as to fulfill the seven awakening factors.