(Radha Raman, Vrindavan—click to enlarge)
Prabhupāda: A spiritual master means voluntarily accepting a great personality whose rules and regulation he must abide by. This is accepting of spiritual master, voluntarily accepting somebody, "Yes, sir. Whatever you'll say, I'll accept." Śiṣya. Śiṣya means who abides by the rules. That is called śiṣya. Or English, "discipline." From discipline, disciplic, disciplic succession. From the discipline. So either you take English or Sanskrit, the same meaning. Śiṣya means who accepts the ruling of his spiritual master; and disciple means also the same thing: who becomes disciplined by the spiritual master.
So tapasya means even at the inconvenience of my personal comforts, I must abide by the orders of my spiritual master. This is called tapasya. And who is spiritual master? He does not manufacture any rules and regulation. He refers to the śāstra. Therefore Narottama dāsa Ṭhākura says, sādhu-śāstra-guru-vākya, tinete kariyā aikya. If you want to know who is a spiritual master, if you know who is a saintly person, then you should keep in the middle the śāstra, the scriptures, and you will corroborate. The saintly person, the spiritual master and the śāstra corroborate if they are abiding one another. Yes. If spiritual master says something which is not in the śāstra, or scripture, that is not good. Of course, sometimes we do not... we cannot understand; but that is the principle. Similarly, a saintly person also, a mahātmā also, cannot disregard the regulative principles of śāstra. In the Bhagavad-gītā it is said, yaḥ śāstra-vidhim utsṛjya (BG 16.23) "A person who gives up obedience to the ruling of the scriptures," yaḥ śāstra-vidhi... vartate kāma-kārataḥ, "and he acts in his own way, by his whims," na siddhiṁ sāvāpnoti, "he cannot attain perfection." These are the versions of Bhagavad-gītā. Na siddhiṁ sāvāp... na sukham: "And at the same time, he cannot be happy." Na parāṁ gatim: "And what to speak of liberation?"
So therefore this tapasya (austerity) means voluntarily accepting the rulings of scriptures, spiritual master, saintly person, and mold your life in that way. So He (Mahārāja Ṛṣabhadeva) is instructing His sons, "My dear sons, don't spoil your life living like cats and dogs and hogs. Utilize your life by tapasya, by voluntarily accepting the rulings of śāstra, spiritual master, saintly person." The question may be "Why this injunction? Why I shall not live like an animal? And why I have to live under the regulative principles of scriptures and saintly person and spiritual master?" The answer is also there: tapo divyam. Tapo divyaṁ putrakā (SB 5.5.1), "My dear sons, this form of life should be utilized for tapasya." Why? Yena sattvaṁ śuddhyet: "If you accept these principles of life, then your existential condition will be purified." At the present moment we are contaminated by the material nature, modes, mostly ignorance and passion. So He's advising that if you abide by the rulings of tapasya, then your existential condition will be purified. Yena sattvaṁ śuddhyet.
Then the question may be, "What is the use of purifying?" The answer is also there: yena sattvaṁ śuddhyed yasmād brahma-saukhyaṁ tv anantam (SB 5.5.1). "And when your existential condition will be purified, then you will be situated on the transcendental platform of blissful life." And one may question, "What is that?" ...na brahma-saukhyam anantam. You are hankering after happiness, pleasure. So when your existential condition will be purified and you will be placed in the transcendental platform, at that time you will enjoy eternal happiness. You are all... after all, you are after happiness. Why you are struggling so much hard in this material existence? For happiness. Why you are after sense gratification? For happiness. Why you want to possess? For happiness. Why you want to become beautiful? For happiness. Why you want to eat so many things? For happiness. You go on. The happiness, your ultimate goal.
But the happiness which you are now deriving from the sources you have manufactured, that is temporary. If you want to become happy by intoxication, how long? That is temporary. Any way. If you want to be happy by sex indulgence, how long? That is also for a few minutes, few seconds. But if you want eternal, continued happiness, then you have to purify your existentional condition, you have to place yourself in the transcendental position, and you will feel that happiness. Therefore in another place, there is a version by the yogī... by the Śrīmad-Bhāgavatam, ramante yogino 'nante. The yogīs, they are also having sense gratification. But where? Anante: "with the Supreme." They are also having sense gratification. Ramaṇa. Ramaṇa. Ramaṇa means sense gratification. Just like Kṛṣṇa's name is Rādhā-Ramaṇa. His sense gratification is with Rādhārāṇī. So the sense gratification is also there, but not this sense... don't consider like this. Here it is only... sense gratification is a perverted reflection of the spiritual sense gratification. The whole devotional line of service is also sense gratification.
Hṛṣīkeṇa hṛṣīkeśa-sevanam (CC Madhya 19.170). Hṛṣīka means senses, and Hṛṣīkeśa means the master of the senses. The master of the senses is Kṛṣṇa. So when your senses will be applied for the sense gratification of Kṛṣṇa, that is your transcendental position. And when your senses will be employed for your sense gratification, that is material. This is the difference. So when one is situated in the transcendental platform, when one's existential conditions are purified by tapasya, by voluntarily accepting austerity and penance under the guidance of spiritual master, śāstras, scriptures, saintly person, at that time it will be possible that you are in the platform of satisfying the senses of Kṛṣṇa and you are fully satisfied. How it is? The practical example I have given several times, that in this body there are different parts of the body. The different parts of the body cannot enjoy senses or satisfy independent. The different parts of the body will depend on the whole body. You can catch up an nice cake, foodstuff, but the fingers, the parts of the body, cannot enjoy it. But if the fingers catch it and puts into the mouth, it goes to the stomach. Then there is some secretion from the stomach, and it goes to the heart, it turns into blood, it is transfused in different parts of the body, and immediately your finger becomes red. This is the process. Tapo divyaṁ yena (SB 5.5.1). Sense gratification is there, but through Kṛṣṇa. Then you feel complete sense gratification. Just like the gopīs, perfect. All devotees, but gopīs are the supreme.
So this is the process of human life, that we have to purify our present existential condition by voluntarily accepting the regulative principle given by the spiritual master, śāstras. Then we become purified. At that time our senses are employed in the service of the Supreme, and we actually enjoy our senses.
(Srila Prabhupada Lecture, London, September 12, 1969)