Na hi gopyam hi sadhunam: "Sadhu, those who are saintly person, for them there is no secret." There is no secret. There is no privacy. A sadhu has no privacy. Just now in our ordinary social affairs, there is difference between private life and his public life. Now, if somebody is teacher… Now, he is very good teacher, he can explain very nicely a subject matter, but his private life is not very good, then he is not a teacher, he is not a sadhu. That is Vedic conception. One must be a teacher according to his own behavior in life. There is no secrecy or privacy. Now, we think that "We don't mind what is private character. We don't mind. We are concerned with his teaching." No. That sort of teaching will not have any effect. Caitanya Mahaprabhu said, apani acari prabhu jiveri siksaya: a teacher must demonstrate in his practical life what he is teaching. That is the meaning of acarya.

From Srila Prabhupada's Govardhana Puja Lecture in New York on November 4, 1966