Srimad-Bhagavatam: Canto 10 - Chapter 1 - Verse 40
Sanskrit:
निन्दां भगवत: शृण्वंस्तत्परस्य जनस्य वा ।ततो नापैति य: सोऽपि यात्यध: सुकृताच्च्युत: ॥ ४० ॥
ITRANS:
nindāṁ bhagavataḥ śṛṇvaṁstat-parasya janasya vātato nāpaiti yaḥ so ’piyāty adhaḥ sukṛtāc cyutaḥ
Translation:
Anyone who fails to immediately leave the place where he hears criticism of the Supreme Lord or His faithful devotee will certainly fall down, bereft of his pious credit.