If we purify our consciousness by advancing, by developing Kṛṣṇa consciousness, then we become pure. This is the process of Kṛṣṇa consciousness movement. Ceto-darpaṇa-mārjanam (CC Antya 20.12), Caitanya Mahāprabhu says. Cleansing the heart. And all these purificatory methods, they are based on cleansing the heart. If I think myself that, "I am something of this material product . . ." The scientists, they say that "I am these material thing." They do not understand what is spiritual identity. And I do, I act, according to that material conception—that is impurity of my consciousness. First thing is to understand that "I am not this material body."
Therefore, spiritual education begins from this body. As Kṛṣṇa says in the Bhagavad-gītā, dehino 'smin yathā dehe (BG 2.13). Asmin dehe, in this body there is the spiritual spark who is the proprietor of the body. This is the beginning of spiritual education. What is the scientists cannot imagine, or they have no idea, from there we begin our education in spiritual life—beyond their jurisdiction, beyond the jurisdiction of the scientists. And how they can understand this movement? It is beyond their jurisdiction. When they will receive one hundred or one thousands of Nobel Prize, at that time they may be able to understand that where Kṛṣṇa consciousness movement begins. They do not know even where the Kṛṣṇa consciousness movement begins.
Therefore, generally people cannot understand what is this Kṛṣṇa consciousness movement. They think it is some religious sentiment, like so many other religion—it is like that. No. It is most the scientific movement, purifying the existence of the living being so that he can eternally, blissfully live, with complete knowledge. That is Kṛṣṇa consciousness movement. To purify. Yena śuddhyet sattvam (SB 5.5.1).
And for such . . . just like for being cured from your attack of cold and cough, you take so many medicines, go to so many physician, you spend some money. Why? You want to be cured. Similarly, if you understand that "This is my disease, repetition of birth, death, old age and disease," so you'll have to sacrifice. Just like you are sacrificing money for being cured from the diseased condition, similarly, śāstra says that this human life is meant for tapasya, tapasya. Tapo divyaṁ yena śuddhyet sattvam (SB 5.5.1). This human life is meant for tapasya, not for indulging in sensual gratification like the animals. Tapasya. So in the tapasya method these things are prescribed. So Yudhiṣṭhira Mahārāja is mentioning them.
So this Kṛṣṇa consciousness movement means training people how to become tapasvī. Tapasvī means undergoing tapasya, regulative, so that he may be cured from this permanent disease—birth, death, old age and disease. The Kṛṣṇa consciousness movement . . . the whole Vedic process is meant for that purpose, to purify the existence of the living being so that he can be saved from the repetition of birth, death, old age and disease.