Sense control through devoted service to the spiritual master liberates one from material bondage rooted in sex desire.Listen — Srila Prabhupada Uvaca
Pradyumna: Oṁ namo bhagavate vāsudevāya. Oṁ namo bhagavate vāsudevāya. Oṁ namo bhagavate vāsudevāya. [devotees repeat] [chants verse; devotees respond] [break] brahmacārī guru-kule vasan dānto guror hitam ācaran dāsavan nīco gurau suḍṛdha-sauhṛdaḥ [SB 7.12.1] [01:23] Translation: "Nārada Muni continued to speak that the student should completely practice how to control the senses, be submissive.
Firmly in friendly attitude upon the spiritual master, with great vow, the brahmacārī should live at gurukula only for the benefit of the guru." Prabhupāda: brahmacārī guru-kule vasan dānto guror hitam ācaran dāsavan nīco gurau suḍṛdha-sauhṛdaḥ [SB 7.12.1] So as it is stated that human life is meant for tapasyā, austerity. Tapasā. Tapo divyaṁ putrakā yena śuddhyet sattva [SB 5.5.1], that this human form of life is meant for tapasyā, not to live like cats and dogs. That is not human form of life.
And tapasyā, austerity, begins from brahmācārya. Tapasā brahmacaryeṇa śamena damena vā [SB 6.1.13]. This is tapasyā. Brahmacarya means restraining sex life, celibacy.
That is brahmacarya. So when one is serious about advancement of spiritual consciousness, he must live under the control of the guru to learn how to become brahmacārī. This is the main purpose. The whole Vedic civilization is on the basis of controlling the senses. The yoga practice, it is also meant for controlling the senses.
Yoga indriya-saṁyamaḥ. By some artificial bodily exercise one can control the senses. That is called yoga. But one who becomes directly a devotee, his sense control is automatically done, if he is devotee.
Bhaktiḥ pareśānubhavo viraktir anyatra syāt [SB 11.2.42]. If one is devotee, then he does not like anything material. And the sex enjoyment is the topmost pleasure in this material world. So naturally one who is devotee, he doesn't require to practice brahmacarya separately—paraṁ dṛṣṭvā nivartate [Bg 2.59], because sex pleasure may be very nice in this material world, but when one gets a sense of spiritual pleasure, then this pleasure becomes abominable.
It is said by Yāmunācārya, yad-avadhi mama cetaḥ kṛṣṇa-padāravindayor nava-nava-dhāmany rantum āsīt tad-avadhi bata nārī-saṅgame bhavati mukha-vikāraḥ suṣṭu niṣṭhīvanaṁ ca "Since I have begun to understand Kṛṣṇa consciousness and getting relish, then, since then, when I think of...," bata nārī-saṅgame, "sex pleasure with woman, I spit on it and my mouth becomes curved, 'Eh,' like that." Actually it is the position, but because we are under the spell of māyā, we are captivated, bewildered, that after sex life, not only human being, but anyone who is living within this material world, beginning from Brahmā down to the smallest insect, everyone is after sex life. We have heard that even Lord Śiva, Lord Brahmā, they became sexually excited. It is said that Lord Brahmā was enchanted by daughter, what to speak of others. This material world is so, I mean to say, bewildering, that sometimes the first-class person also becomes bewildered by sex life.