How does one become sincere?

Bhagavat : At the end of the talk, Prabhupada asked if anybody had questions. I said, "How does one become sincere?" because I thought that sincerity was the key quality in achieving self-realization. He said, "You become sincere by being sincere. You have to want Krishna consciousness. You have to sincerely want to surrender to a spiritual master and to Krishna," and he talked a little about those things. Later on, once in Africa and once in India, I came into Srila Prabhupada's room to see him when some Life Members were present. He introduced me by saying, "This is my disciple, Bhagavat das, and he is very sincere." That struck me. It touched my heart that Prabhupada remembered that I wanted to be sincere.