Because everything is within the heart. We become greedy, we become lusty on account of distortion of the heart disease, kāma. Tadā hṛdi lobha-kāma apahinoti. That is a heart disease. This kāma and lobha is a heart disease. Actually, you don't require this, but it is a kind of disease. "More and more and more and more and more." Never satisfied. So we have to cure this disease. And this process, simple process, Caitanya Mahāprabhu has given: ceto-darpaṇa-mārjanam (CC Antya 20.12). To cure the heart disease of lusty desires and greediness is chanting Hare Kṛṣṇa mahā-mantra. Paraṁ vijayate śrī-kṛṣṇa-saṅkīrtanam. These are the śāstric injunction, and spoken by personalities like Lord Caitanya and other ācāryas.
So we have to follow. Mahājano yena gataḥ sa panthāḥ (CC Madhya 17.186). Don't follow rascals and fools. Then it will be useless waste of time. Follow the great ācāryas. Ācāryavān puruṣo veda. One who is ācāryavān, who has accepted ācārya, he knows. Others, all are fools, rascals. Ācāryavān. Ācāryopāsanam. In the Bhagavad-gītā it is said, amānitvam adambhitvam ahiṁsā kṣāntir ārjavam, ācāryopāsanam (BG 13.8). You have to first of all worship the ācārya. Tad-vijñānārthaṁ sa gurum evābhigacchet (MU 1.2.12). Guru and ācārya, the same thing. So these are the process. Mahājano yena gataḥ. You cannot manufacture your ways of thinking. What you are? You are most insignificant living entity. And without following the ācāryas, without following the mahājanas, without following the śāstra, how you can teach?
But people are doing that. Without being followed by the ācārya, without being followed by the śāstras, they become guru, they become svāmī, they become yogī. It is useless. You cannot get . . . here are the process. Process is given: tadā rajas-tamo-bhāvāḥ kāma . . . (SB 1.2.19). Tadā means when you are fixed up in devotional service, then you can get out of these infection. These are infection. In . . . it is so dangerous infection. Infection, anyone can understand nowadays, scientific days. If you infect some disease, you have to suffer. You cannot escape. You infect today somehow or other—not today, not tomorrow, but some day it will come out. It is called kūṭastha, phalonmukha, prārabdha, pāpa-bīja. Pāpa-bīja remains as seed, kūṭastha. Then it is fructifying, phalonmukha. Then you suffer, prārabdha. This is called prārabdha-karma, infection.
You are under the complete subjugation of nature. Prakṛteḥ kriyamāṇāni guṇaiḥ karmāṇi sarvaśaḥ (BG 3.27). These guṇaiḥ. The prakṛti is forcing you to work because you have infected a kind of guṇa. Kāraṇaṁ guṇa-saṅgo 'sya sad-asad-yoni-janmasu (BG 13.22). Kāraṇam. Why one man is born, one living entity is born as a very rich man and one is born as a dog? Sad-asad-yoni. Yoni means mother, and bīja means father. Yathā yoni yathā bījaḥ. So the every living entity is born bīja and yoni, father and mother. So why there are varieties? Nature is working. Why not one, one kind of living entity? No. Sad-asad-janma-yoniṣu. There are 8,400,000's of species. One has to take. Tathā dehāntara-prāptiḥ (BG 2.13). You have to change. But why one is in the lower grade birth, why in the higher grade? Now, kāraṇaṁ guṇa-saṅgo 'sya. These guṇa. These guṇa, sattva-guṇa, rajo-guṇa.
So we have to give up the association of rajo-guṇa and tamo-guṇa. Then there is question of progress. Otherwise it is simply bluff. Therefore in our Society we say, "Don't associate . . . don't be infected by this rajo-guṇa, tamo-guṇa." This meat-eating and illicit sex life and drinking and gambling, they are rajo-guṇa, tamo-guṇa. Kāma-lobha. You see? There is a big rest ground, gambling, tamo-guṇa. They are going there. Thousands and thousands of people are going there for gambling. This is tamo-guṇa. Why? Lobha, "I must get more money. I must get more money." Lobha, kāma. Kāma-lobhādayaḥ. So we have to get out of all this entanglement. Then there is spiritual life. Otherwise, don't talk of spiritual life.