We should befriend and offer special respect to persons who are developed in Krsna consciousness. Other living entities are undoubtedly part and parcel of the Supreme Lord, but because their consciousness is still covered and not developed in Krsna consciousness, we should renounce their association. It is said by Visvanatha Cakravarti Thakura that even if one is a Vaisnava, if he is not of good character his company should be avoided, although he may be offered the respect of a Vaisnava.

From Srila Prabhupada’s purport to SB 3.29.16