Prabhupāda: ...otherwise, in his preaching, he never stressed. He said,
- kibā vipra kibā nyāsī śūdra kene naya
- yei kṛṣṇa-tattva-vettā sei guru haya
- (CC Madhya 8.128)
"It doesn't matter whether he's a sannyāsī or gṛhastha or a brāhmaṇa or śūdra; it doesn't matter. If he knows the science of Kṛṣṇa, then he's all right." So this is very reasonable. One requires to know the science. (Hindi) People are interested in whether he knows medical science. That's all. He may be a brāhmaṇa, a śūdra. It doesn't matter. Similarly, Kṛṣṇa consciousness means one should be Kṛṣṇa conscious. He should know the science of Kṛṣṇa. Then he's all right. It doesn't matter what he is. Caitanya Mahāprabhu... Just like Śaṅkarācārya, (Hindi) First of all, you become sannyāsa. Then you talk of spiritual thing. That was his condition. And he would simply offer sannyāsa to the caste brāhmaṇa. Nobody else. Stricture. But Caitanya Mahāprabhu is very liberal, that "Either you become sannyāsī or gṛhastha, it does not matter. You must know the science of Kṛṣṇa. Then you can act as spiritual master. You must know the science of Kṛṣṇa."