SB 7.10.19
yatra yatra ca mad-bhaktah
prasantah sama-darsinah
sadhavah samudacaras
te puyante ’pi kikatah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
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 by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Wherever exalted devotees stay, not only they and their dynasties but the entire country is purified.