Janmanā jāyate śūdra—by birth everyone is a Śūdra, illiterate, without any knowledge. He is called Śūdra, worker class. Illiterate maybe, but without any sufficient knowledge. He is called a Śūdra. So everyone is born Śūdra. By the father and mother, when one is born, he is to be accepted as a Śūdra, uncultured. Janmanā jāyate śūdraḥ saṁskārād bhaved dvijaḥ: by education, by reformation, he is become a dvija. Dvija means twice-born.
Just like the bird. Bird is called also dvija, because the bird is once born within the egg, and then fermentation of the egg, he comes out from the egg. Similarly, a person born by the father and mother is a Śūdra, but when he is given education up to the understanding of knowing the Absolute Truth, he becomes dvija, twice-born. Janmanā jāyate śūdraḥ saṁskārād bhaved dvijaḥ veda-pathād bhaved vipra.
And after becoming twice-born . . . you know, you have seen sacred thread, that sacred thread is the emblem that he has approached a spiritual master and his birth has . . . second birth has been performed. This is the badge, a sacred thread—perhaps you've seen Indian Brāhmin. A sacred thread means that is the mark that this man has now twice born. Saṁskārād bhaved dvijaḥ. There are ten kinds of reformatory method, and one of them is initiation from the spiritual master. That is called dvija. Saṁskārād bhaved dvijaḥ.
Veda pathād bhaved vipra, and when he is allowed to study this Vedic literature . . . without becoming dvija, one cannot understand this Vedic literature. Just like without becoming a graduate, you are not allowed to enter in the law court. Similarly, without becoming a dvija, you are not allowed to study the Vedas, because you will not understand. Saṁskārād bhaved dvijaḥ veda-pathād bhaved vipro. And when by studying the Vedic literature he understands Kṛṣṇa, then he becomes a Brāhmin. Vedaiś ca sarvair aham eva vedyam (BG 15.15).
Because the purpose of studying Vedas means to understand Kṛṣṇa, or God. When I speak of Kṛṣṇa, you understand God. So when one understands what is God, what is Brahma, what is Kṛṣṇa, what is Paramātmā, then he is a Brāhmin. This is the process. So the Garga Upaniṣad says that anyone who dies after becoming a Brāhmin, his life is successful. And anyone who dies without becoming a Brāhmin, he dies like a cat and dog. That is the difference.