Qualification through devotion, not birth, determines one's spiritual authority and role in Caitanya's universal mission.Listen — Srila Prabhupada Uvaca
Prabhupāda: The mantra, namaḥ apavitraḥ pavitro vā sarvāvasthāṁ gato 'pi vā yaḥ smaret puṇḍarīkākṣaṁ sa bahyābhyantaraḥ śuciḥ [Garuḍa Purāṇa] So this purificatory process... According to Vedic system, there is purificatory process. Janmanā jāyate śūdraḥ: "By birth everyone is born a śūdra." A śūdra means without any knowledge and simply full of lamentation. Śocati. So the Vedic process is that from the low-grade position, to bring the human society to the highest, topmost position.
Generally it is... The first, topmost position is to become a brāhmaṇa in the society. Cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ [Bg 4.13]. Four divisions of the social system are there, according to quality and work. That is very natural in this world.
Everyone is accepted on quality and work. If you have got a qualification of a good lawyer and if you have done very nicely your activities, then you are selected as the high-court judge. The high-court judge is selected amongst the lawyers in the court. It is not appointed from outside.
The... A lawyer who has done his legal profession very nicely, the government offers him the post, that "You become a high-court judge." So this quality and work is estimated everywhere and in all circumstances. So Bhagavad-gītā recommends—Kṛṣṇa says personally, the Supreme Personality of Godhead—cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ [Bg 4.13]. So that process is applicable at all times.
And Nārada Muni, he also gave description to Yudhiṣṭhira Mahārāja while they were talking about the varṇāśrama. So Nārada Muni gave different symptoms of different varṇa: brāhmaṇa, kṣatriya, vaiśya, śūdra. Then, at the conclusion, he said, yasya hi yal lakṣaṇaṁ proktaṁ varṇābhivyañjakam yady anyatrāpi dṛśyeta tat tenaiva vinirdiśet [SB 7.11.35] He said that "I have already explained the different symptoms of different varṇas—brāhmaṇa will be like that; kṣatriya will be like that; vaiśyas will be like that; śūdras will be like that—so," he says, "if these symptoms are found," anyatra... Suppose one is not born in the brāhmaṇa family—he might have taken birth in a lower family—but he has acquired...
If he has acquired the qualities of a brāhmaṇa, he should be accepted as brāhmaṇa. This is the process. Or if one is born in a brāhmaṇa family but he has not attained the qualities, neither he is working as a brāhmaṇa, then he should be accepted either kṣatriya, vaiśya and śūdra. So this is the system.
So Caitanya Mahāprabhu also wanted to introduce this system. kibā śūdra kibā vipra nyāsī kene naya yei kṛṣṇa-tattva-vettā sei guru haya [Cc Madhya 8.128] He never accepted this, that by birth. No. Either he is a brāhmaṇa or he is a śūdra, by caste or by birth, kibā vipra kibā śūdra nyāsī kene naya; either he's a gṛhastha or a sannyāsī, it doesn't matter. He can become a guru.