Srimad-Bhagavatam: Canto 7 - Chapter 1 - Verse 19

Sanskrit:

यत्र यत्र च मद्भ‍क्ता: प्रशान्ता: समदर्शिन: ।साधव: समुदाचारास्ते पूयन्तेऽपि कीकटा: ॥ १९ ॥

ITRANS:

yatra yatra ca mad-bhaktāḥpraśāntāḥ sama-darśinaḥsādhavaḥ samudācārāste pūyante ’pi kīkaṭāḥ

Translation:

Whenever and wherever there are peaceful, equipoised devotees who are well-behaved and decorated with all good qualities, that place and the dynasties there, even if condemned, are purified.

Purport:

Wherever exalted devotees stay, not only they and their dynasties but the entire country is purified.