Bhakti-yoga process is described in the previous verses. Real purport is karmāśayam, how to be free from karmāśayam. So long our mind will be absorbed in karmāśayam, then there is no question of becoming free from this material body. Karmānubandhaṁ na mucyate deha-yogena tāvat. This is already advised. The whole purpose is how to make the spirit soul from the bondage of contamination of repetition of birth and death. That is the purpose of human life. Karmāśayam: everyone is trying to become happy by working hard and getting the result. Ābrahma-bhuvanāl lokāḥ (BG 8.16): not only here, but also in other planets up to the Brahmaloka, this process is going on. And to counteract this process, in the previous three verses it has been explained how one can gradually become relieved. The first process is recommended, haṁse gurau mayi bhaktyānuvṛtyā.
So this is the Vedic injunction. If you want to understand this science . . . It is science; it is not sentiment. Bhakti-yoga is not sentiment, it is a science. Therefore we have to take it from authorized Vedic instruction. Śrīla Rūpa Gosvāmī has advised that science means you have to take it from the Vedic knowledge. Vedic knowledge means there is no mistake, there is no cheating, there is no imperfection. Everything is perfect. So science means which is perfect knowledge. Not "perhaps," "it may be"; that is not science—theory. Theory is not science. Science, the most important items of science is observation and experiment: first of all to study the situation by observation, and then practically, when you are able to make an experiment, then it is science. Otherwise, theoretical knowledge has no meaning.
So in order to know that science, one has to approach a perfect teacher. Tad-vijñānārthaṁ sa gurum evābhigacchet (MU 1.2.12). Here also it is said, gurau haṁsa. Haṁse gurau mayi. The mayi is also significant. That means . . . paramahaṁsa guru means he's as good as the Supreme Personality of Godhead, because he does not deviate from the instructions of the Supreme Personality of Godhead. That is the symptom of guru. Guru does not deviate from the instruction of the Supreme Personality of Godhead. He does not manufacture something new, novel. No, the same thing. Just like Kṛṣṇa says in the Fourth Chapter, although He is the speaker, millions of years ago He instructed the science to sun god, and again when He was instructing to Arjuna, He said that "I am instructing the same thing." Sa evāyaṁ purātanaḥ (BG 4.3). Not that on account of change of time, the instruction has been changed. No. (aside:) What is that exact verse? Sa evāyaṁ purātanaḥ?
Devotee: Yogaḥ proktaḥ purātanaḥ.
Prabhupāda: Yogaḥ proktaḥ purātanaḥ. Purātanaḥ, not something new. This is nonsense. There cannot be anything new. Everything established. Science means . . . scientific knowledge means it is not something new. Just like the sun rises from the eastern horizon. So millions of years ago, the sun used to rise from the eastern horizon - still it is going on. Not that because time has changed, the sun is rising from the western side or northern side. No. Knowledge means . . . That is Vedic knowledge: established knowledge. It cannot be changed in any circumstances. That is Vedic knowledge. What was millions of years ago fact, it is fact now. So, tad-vijñānārthaṁ sa gurum evābhigacchet (MU 1.2.12). So in order to know that factual knowledge, one has to approach the bona fide spiritual master.
We have several times explained this, who is bona fide spiritual master, confirmed by Caitanya Mahāprabhu. Caitanya Mahāprabhu said that āmāra ājñāya guru hañā, "You become a guru on My instruction." So those who are affiliated with Caitanya Mahāprabhu's instruction, he is guru. Not anyone else. Āmāra ājñāya guru hañā tāra' ei deśa (CC Madhya 7.128). Then one may argue that if Caitanya Mahāprabhu is ordering, then anyone can order? No, Caitanya Mahāprabhu is not ordering something new. Caitanya Mahāprabhu says that "Under My instruction you become guru." But the instruction is Kṛṣṇa's, the same instruction, yāre dekha tāre kaha kṛṣṇa-upadeśa (CC Madhya 7.128). Caitanya Mahāprabhu also does not deviate from Kṛṣṇa's upadeśa, what to speak of others. And those rascals who are deviating from the instruction of Kṛṣṇa, how he can become guru? They are interpreting in a different way, how they can become guru? That is not guru. We should simply remember this fact: whether this person is speaking the same thing as Kṛṣṇa says, as Caitanya Mahāprabhu says, as Rāmānujācārya says, even Śaṅkarācārya.
He, superficially he might have said something which is not understandable, but he also followed the same thing: bhaja govindaṁ bhaja govindaṁ bhaja govindaṁ mūḍha. But due to unfavorable time, he had to say about impersonal feature. But ultimately he said, bhaja govindaṁ bhaja govindam, bhaja govindaṁ mūḍha mate: "You rascal, you just worship Govindam." And this jugglery of words, grammatical jugglery, will not help you at the time of death. Nahi nahi rakṣati dukṛn-karaṇe. If you misinterpret, that "With this grammatical addition or grammatical alteration this meaning can be derived," no. That is malinterpretation. Real understanding is bhaja govindam. Govindam ādi-puruṣaṁ tam ahaṁ bhajāmi. Lord Brahmā, he also says, govindam ādi-puruṣaṁ tam ahaṁ bhajāmi. And Śrīpāda Śaṅkarācārya, he is incarnation of Śaṅkara, he also saying, govindam, bhaja govindam bhaja govindam bhaja govindam. And we are following the same thing, so that is guru-paramparā, that is real knowledge. So don't approach a cheater, but actually approach a teacher, not a cheater. Then bhakti-yoga will be . . . That teacher is guru, and he is representative of Kṛṣṇa. He does not say anything else.
So bhaktyā anuvṛtyā. Anuvṛtyā means following. Not that I have become more than my guru, I can invent something. No. Bhakti means sādhu-mārgānugamanam (CC Madhya 22.115). You have to follow the sādhu, the ācārya. That is bhakti. Bhakti does not mean that I am so learned I can manufacture something. That is rascal. Caitanya Mahāprabhu says, gopī-bhartuḥ pada-kamalayor dāsa-dāsa-dāsa-dāsānudāsaḥ (CC Madhya 13.80). That is bhakti. You have to become servant of the servant of the servant of the servant. Not that at a point you become suddenly very learned scholar, and you do not remain a servant, but you want to become a master, to dictate the guru. That is rascal. That will not help us. Here it is said, bhaktyānuvṛtyā (SB 5.5.10). Bhaktyā, bhaktyā . . . bhakti means sevā. Bhaja sevayā. When bhakti, bhaja dhatu ukti . . . Bhaja means sevayā. Tad viddhi praṇipātena paripraśnena sevayā (BG 4.34). So we have to understand this bhakti-yoga by bhaktyānuvṛtyā, not otherwise. Not that "I am very learned scholar, I can give a different interpretation and . . ." No, that is not bhakti. Bhaktyānuvṛtyā vitṛṣṇayā dvandva-titikṣayā ca (SB 5.5.10).
Then mat-karmabhir mat-kathayā ca nityam (SB 5.5.11). This is a very important word, nityam, mat-kathayā. The Bhagavān says, "My words," so kṛṣṇa-kathā, mat-kathā. Kṛṣṇa says mat-kathā; we can say kṛṣṇa-kathā. So kṛṣṇa-kathā. Kṛṣṇa is speaking personally Bhagavad-gītā, this is kṛṣṇa-kathā. Kṛṣṇa is speaking the words, that is kṛṣṇa-kathā. And Śrīmad-Bhāgavatam also kṛṣṇa-kathā: it is spoken about Kṛṣṇa. Janmādy asya yato 'nvayād itarataś cārtheṣv abhijñaḥ (SB 1.1.1). Paraṁ satyaṁ dhīmahi, that is paraṁ satyam, kṛṣṇa-kathā. Bhagavān is paraṁ satyam, Paraṁbrahman. Not only Brahman, Paraṁbrahman. The Māyāvādī philosophers, they are concerned with the brahman-kathā, but we, very interested not only brahman-kathā but parabrahman-kathā, that is Kṛṣṇa consciousness. That is wanted. Paraṁ brahma paraṁ dhāma pavitraṁ paramaṁ bhavān (BG 10.12). So kṛṣṇa-kathā. Caitanya Mahāprabhu also says, yāre dekha tāre kaha kṛṣṇa-upadeśa (CC Madhya 7.128). This is guru. Kṛṣṇa-kathā. So here it is said that mat-kathā, mat-karmabhir mat-kathayā ca. So . . . And how? Mat-karmabhir mat-kathayā ca nityam, twenty-four hours. Nityam means always. Not that officially, I attend bhāgavata-kathā for seven days or ten days in a year, and there are 365 days, and other 355 days I go to the share market and simply inquire about the rates of this share and that share. That will not help us. Nityaṁ bhāgavata-sevayā (SB 1.2.18), then it is bhakti-yoga.