Bodhāyasutta 
Bodhāyasutta → udāyīvaggo (bj) To Awakening

Atha kho aññataro bhikkhu yena bhagavā tenupasaṅkami …pe… ekamantaṁ nisinno kho so bhikkhu bhagavantaṁ etadavoca:  Then a mendicant went up to the Buddha … and said to him:

“‘Bojjhaṅgā, bojjhaṅgā’ti, bhante, vuccanti.  “Sir, they speak of the ‘awakening factors’.
Kittāvatā nu kho, bhante, ‘bojjhaṅgā’ti vuccantī”ti?  How are the awakening factors defined?”

“‘Bodhāya saṁvattantī’ti kho, bhikkhu, tasmā bojjhaṅgāti vuccanti.  “Mendicant, they’re called awakening factors because they lead to awakening.
Idha, bhikkhu, satisambojjhaṅgaṁ bhāveti vivekanissitaṁ …pe…  A mendicant develops the awakening factors of mindfulness, investigation of principles, energy, rapture, tranquility, immersion,
upekkhāsambojjhaṅgaṁ bhāveti vivekanissitaṁ virāganissitaṁ nirodhanissitaṁ vossaggapariṇāmiṁ.  and equanimity, which rely on seclusion, fading away, and cessation, and ripen as letting go.
‘Bodhāya saṁvattantī’ti kho, bhikkhu, tasmā ‘bojjhaṅgā’ti vuccantī”ti.  They’re called awakening factors because they lead to awakening.”

Paṭhamaṁ.