"It is not that I know everything. I do not know anything, but I, I am surrendered to a person who knows everything. Therefore I know everything. I take my knowledge from Him. So you should think how much knowledge you have assimilated. The knowledge is there, guru-kṛṣṇa. Guru is there. Kṛṣṇa is there. So we have to take advantage of guru and Kṛṣṇa, sad-dharma-pṛcchā, ask him, and become man of knowledge. Then you can say. If you simply think that 'I have my guru, and there is Kṛṣṇa. Now I am perfect,' no. You should ask and know. You must be man of knowledge. Then you can say, 'Yes, I know everything.' Dīkṣā. Dīkṣā, initiation, dīkṣā, this Sanskrit word, dīkṣā, means divya-jñānaṁ kṣipayati. To ask from spiritual master with service and surrender the transcendental knowledge. The more you ask, you become a man of knowledge. Then you can challenge, 'Yes, I know everything.' Hare Kṛṣṇa Hare Kṛṣṇa Kṛṣṇa Kṛṣṇa Hare...
Actually, we know everything. Just like when I speak, I immediately ask reference from Bhagavad-gītā, and we stop the man's argument. So if you become well-conversed with the whole Bhagavad-gītā, then you have full knowledge. There is no need of saying that 'I do not know.' You'll become full knowledge, man of knowledge. But you must study."
(Srila Prabhupada Morning Walk, Paris, June 11, 1974)