SB 12.3.27

prabhavanti yadā sattve
 mano-buddhīndriyāṇi ca
tadā kṛta-yugaṁ vidyāj
 jñāne tapasi yad ruciḥ
Synonyms: 
prabhavanti — they are predominantly manifest; yadā — when; sattve — in the mode of goodness; manaḥ — the mind; buddhi — intelligence; indriyāṇi — senses; ca — and; tadā — then; kṛta-yugam — the age of Kṛta; vidyāt — should be understood; jñāne — in knowledge; tapasi — and austerity; yat — when; ruciḥ — pleasure.
Translation: 
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.
Purport: 

The word kṛta means “performed” or “executed.” Thus in the age of truth all religious duties are duly performed, and people take great pleasure in spiritual knowledge and austerity. Even in the Kali-yuga, those who are situated in the mode of goodness take pleasure in the cultivation of spiritual knowledge and the regulated performance of austerity. This sublime state of existence is possible for one who has conquered sex desire.