Son or anyone, anyone, if he knows the science of Kṛṣṇa, he becomes guru. This is the Vedic system. It doesn't matter. Caitanya Mahāprabhu approved this. Caitanya Mahāprabhu was born in a very respectable brāhmaṇa family. He was very advanced learned scholar, and after all He took sannyāsa. So when He was discussing with Rāmānanda Rāya . . . Rāmānanda Rāya was a gṛhastha, householder, and governor of Madras, means politician. A householder, politician, and he was born not in brāhmaṇa family; in kāraṇa, kāyastha family. They are considered as śūdras. So he had no position to instruct Caitanya Mahāprabhu. But Caitanya Mahāprabhu gave him the place of instructor, and He took the position of a listener. Just see Caitanya Mahāprabhu's pastimes. He gave him the position of instructor, and He took the position of student, listener.
So Rāmānanda Rāya was feeling a little agitation, that "How is that? I am a gṛhastha, householder, not even born in high family, brāhmaṇa family. And I am engaged in politics, I am governor, and He is a sannyāsī, renounced order of life. How is that that He is asking question and I am replying? The question is enquired by the student, and the answer is given by the spiritual master. So how is that?" He was feeling little agitation. So Caitanya Mahāprabhu immediately encouraged him, "Don't hesitate." This is Caitanya Mahāprabhu's example. He is teaching everything by His personal example. His purpose was that in this Kali-yuga the distinction between brāhmaṇa, kṣatriya, vaiśya, śūdra will be almost finished. Then who will instruct? Because the instructor's position is brāhmaṇa. One must be brāhmaṇa. Brāhmaṇa's business is paṭhan pāṭhan yajan yājan dāna pratigraha. A brāhmaṇa should be personally very highly learned scholar. Therefore brāhmaṇa is called paṇḍita. Even in India, still a brāhmaṇa is addressed "Paṇḍitji." He may be a fool number one, but he is addressed like that, "Paṇḍitji." So because without becoming a learned scholar nobody can become a brāhmaṇa . . . we are also giving our student position as brāhmaṇa, but if he remains a fool number one, then we are misusing our attempt. He should be very learned scholar. That should be the aim.