This statement is also confirmed in the Third Canto, Twenty-fifth Chapter, verse 25, of Srimad-Bhagavatam, where Lord Kapila says, "My dear mother, when a person is actually in association with pure devotees, the sublime potency of My devotional service can be experienced." In other words, when a pure devotee speaks, his words act upon the hearts of the audience. What is the secret of hearing and chanting? A professional speaker cannot impress transcendental ecstasy within the hearts of the listeners. However, when a realized soul who is engaged in the service of the Lord is speaking, he has the potency to inject spiritual life within the audience. One should, therefore, seek the association of such pure, unalloyed devotees, and by such association and service a neophyte devotee will certainly develop attachment, love and devotion for the Supreme Personality of Godhead.

(N.O.D. Chapter 17)