Srimad Bhagavatam Canto 11, Chapter 02, Text 44

SB 11.2.44

atha bhagavatam bruta
yad-dharmo yadrso nrnam
yathacarati yad brute
yair lingair bhagavat-priyah
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
Maharaja Nimi said: Now please tell me in greater detail about the devotees of the Supreme Lord. What are the natural symptoms by which I can distinguish between the most advanced devotees, those on the middle level and those who are neophytes? What are the typical religious activities of a Vaisnava, and how does he speak? Specifically, please describe those symptoms and characteristics by which Vaisnavas become dear to the Supreme Personality of Godhead.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada: 
The great sage Kavi has informed King Nimi about the general external symptoms of a devotee of the Lord, namely his appearance, personal qualities and activities. But now King Nimi asks how to make further distinctions among the servants of the Supreme Personality of Godhead so that the first-class, second-class and lower-class Vaisnavas can be clearly identified.
According to Srila Rupa Gosvami, krsneti yasya giri tam manasadriyeta: “One should mentally honor any devotee who chants the holy name of Lord Krsna.” (Upadesamrta 5) Any living entity who is faithfully chanting the holy name of Krsna is to be considered a Vaisnava and at least within the mind is to be offered respect. But for practical advancement in Krsna consciousness one should associate at least with a second-class devotee. And if one can receive the mercy of a first-class devotee of the Lord, one’s perfection is very easily guaranteed. Thus Nimi Maharaja is humbly inquiring, “What are the character, behavior and speech of devotees?” The King wants to know the particular symptoms of body, mind and speech by which the different categories uttama-adhikari, madhyama-adhikari and kanistha-adhikari are clearly identified. In response to the King’s inquiry, another of the nava-yogendras, namely Havir, will give a further elaboration of the science of Krsna consciousness.
Srimad Bhagavatam Canto 11, Chapter 02, Text 43
Srimad Bhagavatam Canto 11, Chapter 02, Text 45