He was asking how do we know what Krsna dictates, by what authority. How do we know how we can serve Krsna?

Expressions researched:
"He was asking how do we know what Krsna dictates, by what authority. How do we know how we can serve Krsna"

Srimad-Bhagavatam Lectures

Yes. That is answered in the Bhagavad-gītā, Fourth Chapter: evaṁ paramparā-prāptam imaṁ rājarṣayo viduḥ. Just like you call this "table." How you understand this is table. You have taken the idea from your parents. And wherefrom your parents got this idea that this is a table? They also got from their parents. Therefore this idea of table, you do not say anything else, is received by succession. Similarly, you can receive succession order from Kṛṣṇa through spiritual master.

Lecture on SB 7.6.3 -- Montreal, June 16, 1968:

Guest (2): Swamijī, I think this man's question needs a little bit more clarification. He was asking how do we know what Kṛṣṇa dictates, by what authority. How do we know how we can serve Kṛṣṇa? Is that your question? How do we know how we can serve Kṛṣṇa?

Guest (1): Yes. Well, I, one thing...

Prabhupāda: That I have answered, that you can serve Kṛṣṇa by following the dictation of Kṛṣṇa. Is it not clear? The next question may be how you receive dictation of Kṛṣṇa. Is that?

Guest (1): Right. Yes. That would be the next question. (laughter)

Prabhupāda: Yes. That is answered in the Bhagavad-gītā, Fourth Chapter: evaṁ paramparā-prāptam imaṁ rājarṣayo viduḥ (BG 4.2). Just like you call this "table." How you understand this is table. You have taken the idea from your parents. And wherefrom your parents got this idea that this is a table? They also got from their parents. Therefore this idea of table, you do not say anything else, is received by succession. Similarly, you can receive succession order from Kṛṣṇa through spiritual master.