Śrīmad-Bhāgavatam · Text 12.3.27
Who is speaking and story frame
प्रभवन्ति यदा सत्त्वे मनोबुद्धीन्द्रियाणि च ।
तदा कृतयुगं विद्याज्ज्ञाने तपसि यद् रुचि: ॥ २७ ॥
prabhavanti yadā sattve
mano-buddhīndriyāṇi ca
tadā kṛta-yugaṁ vidyāj
jñāne tapasi yad ruciḥ
When the mind, intelligence and senses are solidly fixed in the mode of goodness, that time should be understood as Satya-yuga, the age of truth. People then take pleasure in knowledge and austerity.
Read the purport on Vedabase.ioFrom Canto 10, chapter 14 onward, the translation and purports were completed by Śrīla Prabhupāda's disciples after his departure, and published by the Bhaktivedanta Book Trust.