Majjhima Nikaya (Coleção dos Discursos Médios) 3:112
SUJATOTassa taṁ dhammaṁ paññāya pavicinato pavicayato parivīmaṁsaṁ āpajjato āraddhaṁ hoti vīriyaṁ asallīnaṁ.
As they investigate principles with wisdom in this way their energy is roused up and unflagging.