In the Middle Ages, after the disappearance of Lord Caitanya's great associate Lord Nityānanda, a class of priestly persons claimed to be the descendents of Nityānanda, calling themselves the gosvāmī caste. They further claimed that the practice and spreading of devotional service belonged only to their particular class, which was known as Nityānanda-vaṁśa. In this way, they exercised their artificial power for some time, until Śrīla Bhaktisiddhānta Sarasvatī Thākur, the powerful ācārya of the Gauḍīya Vaiṣṇava sampradāya, completely smashed their idea. There was a great hard struggle for some time, but it has turned out successfully, and it is now correctly and practically established that devotional service is not restricted to a particular class of men. Besides that, anyone who is engaged in devotional service is already on the status of being a high-class brāhmaṇa. So Śrīla Bhaktisiddhānta Sarasvatī Thākur's struggle for this movement has come out successful.
It is on the basis of his position that anyone can now become a Gauḍīya Vaiṣṇava, from any part of the world or any part of the universe. Anyone who is a pure Vaiṣṇava is situated transcendentally, and therefore the highest qualification in the material world, namely, to be in the modes of goodness, is already achieved by such a person. Our Kṛṣṇa consciousness movement in the Western world is based on the above-mentioned proposition of Śrīla Bhaktisiddhānta Sarasvatī Gosvāmī Prabhupāda, our spiritual master. On his authority, we are claiming members from all sections of the Western countries. The so-called brāhmaṇas claim that one who is not born into a brāhmaṇa family cannot receive the sacred thread and cannot become a high-grade Vaiṣṇava. But we do not accept such a theory because it is not supported by Rūpa Gosvāmī nor by the strength of the various scriptures.
Śrīla Rūpa Gosvāmī specifically mentions herein that every man has the birthright to accept devotional service and to become Kṛṣṇa conscious. He has given many evidences from many scriptures, and he has especially quoted one passage from Padma Purāṇa, wherein sage Vasiṣṭha tells King Dilīpa: "My dear King, everyone has the right to execute devotional service, just as he has the right to take early bath in the month of Māgh (December-January)." There is more evidence in Padma Purāṇa, in the Kāśīkhaṇḍa portion, where it is said: "In the country known as Mayūradhvaja, the lower caste people who are considered less than śūdras are also initiated in the Vaiṣṇava cult of devotional service. And when they are properly dressed, with tilaka on their bodies and beads in their hands and on their necks, they appear to be coming from Vaikuṇṭha. In fact, they look so very beautiful that immediately they surpass the ordinary brāhmaṇas."
Thus a Vaiṣṇava automatically becomes a brāhmaṇa. This idea is also supported by Sanātana Gosvāmī in his book Hari-bhakti-vilāsa, which is the Vaiṣṇava guide. Therein he has clearly stated that any person who is properly initiated into the Vaiṣṇava cult certainly becomes a brāhmaṇa, as much as the metal known as kaṁsa (bell metal) is turned into gold by the mixture of mercury. A bona fide spiritual master, under the guidance of authorities, can turn anyone to the Vaiṣṇava cult so that naturally he may come to the topmost position of a brāhmaṇa.
Śrīla Rūpa Gosvāmī warns, however, that if a person is properly initiated by a bona fide spiritual master, he should not think that simply by the acceptance of such initiation his business is then finished. One still has to follow the rules and regulations very carefully. If after accepting the spiritual master and being initiated one does not follow the rules and regulations of devotional service, then he is again fallen. One must be very vigilant to remember that he is the part and parcel of the transcendental body of Kṛṣṇa, and it is his duty as part and parcel to give service to the whole, or Kṛṣṇa. If we do not render service to Kṛṣṇa then again we fall down. In other words, simply becoming initiated does not elevate one to the position of a high-class brāhmaṇa. One also has to discharge the duties and follow the regulative principles very rigidly.