Digha Nikaya 2:313
SUJATOuppannānaṁ kusalānaṁ dhammānaṁ ṭhitiyā asammosāya bhiyyobhāvāya vepullāya bhāvanāya pāripūriyā chandaṁ janeti vāyamati vīriyaṁ ārabhati cittaṁ paggaṇhāti padahati.
They generate enthusiasm, try, make an effort, exert the mind, and strive so that skillful qualities that have arisen remain, are not lost, but increase, mature, and are completed by development.