Śrīmad-Bhāgavatam · Text 3.15.23
Who is speaking and story frame
यन्न व्रजन्त्यघभिदो रचनानुवादा-
च्छृण्वन्ति येऽन्यविषया: कुकथा मतिघ्नी: ।
यास्तु श्रुता हतभगैर्नृभिरात्तसारा-
स्तांस्तान् क्षिपन्त्यशरणेषु तम:सु हन्त ॥ २३ ॥
yan na vrajanty agha-bhido racanānuvādāc
chṛṇvanti ye ’nya-viṣayāḥ kukathā mati-ghnīḥ
yās tu śrutā hata-bhagair nṛbhir ātta-sārās
tāṁs tān kṣipanty aśaraṇeṣu tamaḥsu hanta
It is very much regrettable that unfortunate people do not discuss the description of the Vaikuṇṭha planets but engage in topics which are unworthy to hear and which bewilder one’s intelligence. Those who give up the topics of Vaikuṇṭha and take to talk of the material world are thrown into the darkest region of ignorance.
Read Śrīla Prabhupāda's purport on Vedabase.io