Anyone who is well versed in bhagavat-tattva-vijñānam, he's . . . he can become guru. Not others. And in many places this is confirmed, that ṣaṭ-karma-nipuṇo vipro (Padma Purāṇa). A brahmin, very well expert in his business . . . brāhmin's business means ṣaṭ-karma, six kinds of karma: paṭhana pāṭhana yajana yājana dāna pratigraha. A brahmin must be very learned scholar, brāhmin paṇḍita. He must be scholar. Scholar means not ordinary, but in transcendental science. Tad vijñānam. So paṭhana pāṭhana. And he must be expert teacher also. He should not . . .
Actually in our India, formerly, the brahmins, they usually become teachers. In any village, a brahmin has no other business. He sits down. He's called catuṣpāṭhī, the higher scholars. But for ordinary also. A brahmin . . . guru-maharṣayaḥ. We studied under guru-maharṣayaḥ in our childhood. Pāṭha śālā. So anywhere a brahmin can sit down and the village boys, small boys, children would come there. He doesn't charge anything, but their father, mother sends everything—rice, ḍāl, cloth. So he has no much demand for bodily necessities. This was paṭhana. This is brahmin. Brahmin should not accept any service.