According to śāstra, we have prescribed, "No illicit sex, no meat-eating, no gambling, no intoxication." Four no's. Then you become free from sinful activities. And then chant Hare Kṛṣṇa. Your life is successful. It is not very difficult, provided you are serious to take it. So that is our request. Harer nāma harer nāma harer nāmaiva kevalam (CC Adi 17.21). Even if you cannot give up the four principles of sinful life immediately, but you take to Kṛṣṇa consciousness, chant Hare Kṛṣṇa mantra, then you gradually get strength. Just like these European, American boys. From their childhood they are trained up for this sinful life, but they have given up completely. Young men. Still, they have given up.
So the method is very simple. Ceto-darpaṇa-mārjanaṁ bhava-mahā-dāvāgni-nirvāpaṇam (CC Antya 20.12). If we chant Hare Kṛṣṇa mantra, then the mirror of the core of heart will be cleansed. Ceto-darpaṇa-mārjanam. And then bhava-mahā-dāvāgni-nirvāpaṇam. This repetition of birth, death, old age and disease, this is just like a fire in the forest. Nobody wants it, but it is forced up on us. Just like nobody wants to set fire in the forest, but it takes place naturally. Similarly, if you remain in this material world then you have to be, I mean to say, put into these tribulations of materialistic way of life. There is no escape. Saṁsāra-dāvānala. It is just like dāvānala. So ceto-darpaṇa-mārjanaṁ bhava-mahā-dāvāgni-nirvāpaṇam. As soon as you understand that "I do not belong to this material world"—brahma-bhūtaḥ prasannātmā na śocati na kāṅkṣati (BG 18.54)—then all problems of life is solved. Ahaṁ brahmāsmi. This is ceto-darpaṇa-mārjanam (CC Antya 20.12). So as soon as one is cleansed of the dirty things in the heart, then he can understand that "I am part and parcel of Kṛṣṇa. My duty is to serve Kṛṣṇa. So let me be engaged in His service and become successful in this human form of life."