Mahamsa das: I was a brahmacari, I was not even initiated at that time. There was a class going on, and he asked this question in the class. He said, “How do you know that Krishna is God? Why do you believe me?” So some devotee said, “Because it says in the Bhagavad-gita, aham tvam sarva-papebhyo,” and all that, quoting some verses from the Bhagavad-gita. Or saying that because Prabhupada… “No, I may be lying also, I may be lying. How do you know that Krishna is Krishna?” So someone quoted from the Bhagavad-gita some verse. He says, “Yeah, but whether you believe the Bhagavad-gita or not believe Bhagavad-gita, the translation or interpretation may be wrong. How do you know that Krishna is Krishna?” So actually I was a very new devotee at that time. So all the senior devotees were giving their explanation and Prabhupada kept saying, “No, no. This is not a good answer. This is not a good answer. That’s not enough.” And then finally there was a little quietness. I was even afraid to say what I felt like saying, so very meekly I put my hand up and Prabhupada said, “Yes?” And I said, “Prabhupada, I believe it is Krishna because I can feel Krishna. When I say Krishna, I can feel Him, I can feel it. That’s why I believe in it.” And then his eyes grew up like that, “Yes! That is it! You can feel Krishna’s presence, that’s why you believe in Krishna!” And he looked at me with so much happiness that “Yes! Your answer is right.”
Reference: Remembrances by Yadubara Das- Folio Vedabase