No one becomes purified by the association of such persons who are proud, in a position of false prestige, thinking themselves to be a brahmana. Whereas even if a person is born into family of candalas, if he’s a devotee, then immediately he’s considered to be on a far superior platform than a proud brahmana in a position of false prestige. So it was on that basis that Srila Prabhupada expanded the Krishna Conscious movement.
( Unknown time and place. Caitanya Caritamrita)