Revatīnandana: "This faith is attained by the discharge of devotional service, and by chanting Hare Kṛṣṇa, Hare Kṛṣṇa, Kṛṣṇa Kṛṣṇa, Hare Hare/ Hare Rāma, Hare Rāma, Rāma Rāma, Hare Hare, which cleanses one's heart of all material dirt. Over and above this, one should control the senses. A person who is faithful and controls the senses can easily attain perfection in the knowledge of Kṛṣṇa consciousness without delay."
Prabhupāda: Controlling of senses means . . . that is also knowledge. Because this materialistic life means sense gratification. So we have satisfied our senses not only in this human form of life, but in other forms of life. So when one comes to the understanding that these sense gratification activities are useless, then he can understand. When one understands that, "I have tried to satisfy myself in different kinds of sense gratification . . ."
Just like people are trying the same thing which they have got at home . . . just like a naked woman. They are still going to the theater to see naked dance. You see? What is that? They have no idea. The same thing. Punaḥ punaś carvita-carvaṇānām (SB 7.5.30).
Chewing the chewed, trying to find out in which naked dance there is pleasure. That's all. So when one comes to the knowledge that "I have seen so many different types of naked dance and naked woman. What I have got? What I have gained? What satisfaction is there? Why I am not satisfied?" that is knowledge. That is knowledge.
Just like Bilvamaṅgala Ṭhākura. You have heard the story of Bilvamaṅgala Ṭhākura. There are many stories. So he was very much fond of his girlfriend, prostitute. So when one night when he approached there within torrents of rain and with great difficulties, the woman was sympathetic.
She said: "Bilvamaṅgala, you are so much attracted with this flesh and bone. Oh, if you had been so much attracted to Kṛṣṇa, how you would have been." Oh, immediately he turned: "Yes." So he immediately went back and went to Vṛndāvana.
So these are the points of knowledge. You see? One . . . when one is struck with that knowledge that, "What I have gained? I have tried life after life, hours after hours, days after days this sense gratification. What I have got?" this is knowledge. Then searching begins.