(Immeasurable) Concentration
Samādhi Sutta  (AN 5:27)

“Mindful & astute, you should develop immeasurable concentration [i.e., concentration based on immeasurable goodwill, compassion, empathetic joy, or equanimity]. When, mindful & astute, one has developed immeasurable concentration, five realizations arise right within oneself. Which five?

“The realization arises right within oneself that ‘This concentration is blissful in the present and will result in bliss in the future.’

“The realization arises right within oneself that ‘This concentration is noble & not connected with the baits of the flesh.’

“The realization arises right within oneself that ‘This concentration is not obtained by base people.’

“The realization arises right within oneself that ‘This concentration is peaceful, exquisite, the acquiring of calm, the attainment of unification, not kept in place by the fabrications of forceful restraint.’

“The realization arises right within oneself that ‘I enter into this concentration mindfully, and mindfully I emerge from it.’

“Mindful & astute, you should develop immeasurable concentration. When, mindful & astute, one has developed immeasurable concentration, these five realizations arise right within oneself.”

See also: SN 41:7; SN 42:8; AN 3:66; AN 6:13; AN 8:70; AN 11:16; Khp 9; Iti 22; Iti 27; Thag 6:2