मज्झिम निकाय 3:115
SUJATOYasmiṁ samaye, bhikkhave, bhikkhuno āraddhavīriyassa uppajjati pīti nirāmisā, pītisambojjhaṅgo tasmiṁ samaye bhikkhuno āraddho hoti, pītisambojjhaṅgaṁ tasmiṁ samaye bhikkhu bhāveti, pītisambojjhaṅgo tasmiṁ samaye bhikkhuno bhāvanāpāripūriṁ gacchati.
At such a time, a mendicant has activated the awakening factor of rapture; they develop it and perfect it.