Then a certain bhikkhu approached the Blessed One … and said to him: “Venerable sir, it is said, ‘equipped with faculties, equipped with faculties.’ In what way, venerable sir, is one equipped with faculties?”
“If, bhikkhu, while one dwells contemplating rise and fall in the eye faculty, one experiences revulsion towards the eye faculty; if, while one dwells contemplating rise and fall in the ear faculty, one experiences revulsion towards the ear faculty; … if, while one dwells contemplating rise and fall in the mind faculty, one experiences revulsion towards the mind faculty, then, experiencing revulsion, one becomes dispassionate…. When the mind is liberated, there comes the knowledge: ‘It’s liberated.’ One understands: ‘Destroyed is birth, the holy life has been lived, what had to be done has been done, there is no more for this state of being.’ It is in this way, bhikkhu, that one is equipped with faculties.”