Devibhagavatapurana 4.13.6

4.13.6

śabdapramāṇamucchedaṃ śiṣṭābhāve gataṃ na kim |
chalakarmapravṛtte vāvigītatvaṃ gurau katham ||

O Muni! The words sung by the ancient virtuous and respectable sages were true and had their corresponding objects denoted by those words; now they employed the term S’ista meaning that there were virtuous, respectable persons as denoted by them. When Brihaspatî can even commit such condemnable deceitful acts and speak falsehood, we can expect no virtuous respectable persons in the world. Where then do you find the S’ista persons, denoted by the word S’ista, sung by the ancient sages? The word S’ista is now meaningless!