Brahmacarya is different from English term "celibacy," which merely means non-indulgence in sexual activity. Brahmacarya is when a person controls his citta, which does not necessarily mean abstaining through word, thought, and deed from physical or sensual pleasures to achieve Brahmagyan.
In one context, brahmacarya is the first of four ashrama (age-based stages) of a human life, with grihastha (householder), vanaprastha (forest dweller), and sannyasa (renunciation) being the other three asramas. The brahmacarya (bachelor student) stage of life – from childhood up to twenty-five years of age – was focused on education and included the practice of celibacy. In this context, it connotes chastity during the student stage of life for the purposes of learning from a guru (teacher), and during later stages of life for the purposes of attaining spiritual liberation (Sanskrit: moksha).
In the Hindu, Jain, and Buddhist monastic traditions, brahmacarya implies, among other things, the mandatory renunciation of sex and marriage. It is considered necessary for a monk's spiritual practice. Western notions of the religious life as practiced in monastic settings mirror these characteristics.
In ancient and medieval era Indian texts, the term brahmacarya is a concept with a more complex meaning indicating an overall lifestyle conducive to the pursuit of sacred knowledge and spiritual liberation. Brahmacarya is a means, not an end. It usually includes cleanliness, ahimsa, simple living, studies, meditation, and voluntary restraints on certain foods (eating only Sattvic food), intoxicants, and sexual behavior which is no sex (in some schools of thought).
Brahmacarya is traditionally regarded as one of the five yamas in Yoga, as declared in verse 2.30 of Patanjali's Yoga Sutras. It is a form of self-restraint regarded as a virtue, and an observance recommended depending on an individual's context. For a married practitioner it means marital fidelity (not cheating on one's spouse); for a single person it means celibacy. Sandilya Upanishad includes brahmacarya as one of ten yamas in Chapter 1, defining it as "refraining from sexual intercourse in all places and in all states in mind, speech or body".
Patanjali in verse 2.38 states that the virtue of brahmacarya leads to the profit of virya (वीर्य). This Sanskrit word, virya, has been variously translated as virility and, by Vyasa, as strength and capacity. Vyasa explains that this virtue promotes other good qualities. Other ancient and medieval era texts of Hinduism describe the fruits of this virtue differently. For example, Pada Chandrika, Raja Marttanda, Sutrartha Bodhini, Mani Prabha and Yoga Sudhakara each state that brahmacarya must be understood as the voluntary restraint of power. Chandogya Upanishad in verses of chapter 8.5 extols brahmacarya as a sacrament and sacrifice which, once perfected, leads to realization of the soul or Self (Atman), and thereafter becomes the habit of experiencing the soul in others and everything. Tattva Vaisharadi and Yoga Sarasangraha assert that brahmacarya leads to and increase in jñana-shakti (power of knowledge) and kriya-shakti (power of action).
The great epic Mahabharata describes the objective of brahmacarya as knowledge of Brahman (Book Five, Udyoga Parva, the Book of Effort). Brahmacarya leads one to union with the Supreme Soul or Self (Chapter 43). By subduing desire, the practice of self-restraint enables the student to learn, pay attention in thought, word and deed to the guru (teacher), and discover the truth embodied in the Vedas and Upanishads. According to the epic, the practice of studying and learning requires the "aid of time," as well as personal effort, ability, discussion, and practice, all of which are helped by the virtue of brahmacarya. A brahmacārī should do useful work, and the earnings he obtains should be given away as dakshina ("fee," "gift of thanks") to the guru. The epic declares that brahmacarya is one of twelve virtues, an essential part of angas in yoga and the path of perfecting perseverance and the pursuit of knowledge.
Brahmacarya is one of the five major vows prescribed for the śrāvakā (layman) and ascetics in Jainism. For those Jains who adopt the path of monks, celibacy in action, words and thoughts is expected. For lay Jains who are married, the virtue of brahmacarya requires remaining sexually faithful to one's chosen partner. For lay Jains who are unmarried, chaste living requires Jains to avoid sex before marriage. Uttam Brahmacarya (Supreme Celibacy) is one of the ten excellencies of a Digambara monk. Brahmacarya is mentioned as one of the das dharma (ten virtues) in ancient Jain texts like Tattvartha Sutra, Sarvārthasiddhi and Puruşārthasiddhyupāya.
Among the sramanic traditions (Buddhism, Jainism, Ājīvika and Carvaka schools ), brahmacarya is the term used for a self-imposed practice of celibacy generally considered a prerequisite for spiritual practice. The fourth of the five great vows of Jain monks, for example, is the vow of celibacy, which in this case means a total abstinence from the sensual pleasure of all five senses, including the avoidance of sexual thoughts and desires. The yogin who is firmly grounded in the virtue of brahmacarya is said to gain great vitality.
Historically brahmacarya referred to a stage of life (asrama) within the Vedic ashram system. Ancient Hindu culture divided the human lifespan into four stages: Brahmacarya, Grihastha, Vanaprastha and Sannyasa. Brahamacarya asrama occupied the first 20–25 years of life roughly corresponding to adolescence. Upon the child's Upanayanam, the young person would begin a life of study in the Gurukula (the household of the Guru) dedicated to learning all aspects of dharma that is the "principles of righteous living". Dharma comprised personal responsibilities towards himself, family, society, humanity and God which included the environment, earth and nature. This educational period started when the child was five to eight years old and lasted until the age of 14 to 20 years. During this stage of life, the traditional vedic sciences and various sastras were studied along with the religious texts contained within the Vedas and Upanishads. This stage of life was characterized by the practice of celibacy.
Naradaparivrajaka Upanishad suggests that the Brahmacarya (student) stage of life should extend from the age a child is ready to receive teachings from a guru, and continue for a period of twelve years.
Graduation from the Brahmacarya stage of life was marked by the Samavartanam ceremony. The graduate was then ready to either start Grihastha (householder) stage of life, or wait, or pursue a life of Sannyasa and solitude like Rishis in forest. Vyasa in Chapter 234 of Shanti Parva in the Mahabharata praises Brahmacarya as an important stage of life necessary for learning, then adds Grihastha stage as the root of society and important to an individual's success.
ब्रह्मचर्येण कन्या युवानं विन्दते पतिम् | A youthful Kanya (कन्या, girl) who graduates from Brahmacarya, obtains a suitable husband.
Gonda states that there were no age restrictions for the start of Brahmacarya in ancient India. Not only young men, but older people resorted to student stage of life, and sought teachers who were authoritative in certain subjects. The Chandogya Upanishad, in Section 5.11, describes "wealthy and learned householders" becoming brahmacārīs (students) with Rishi Kaikeya, to gain knowledge about Atman (Soul, inner Self) and Brahman (Ultimate Reality).
The Vedas discuss Brahmacarya, both in the context of lifestyle and stage of one's life. Rig Veda, for example, in Book 10 Chapter 136, mentions knowledge seekers as those with Kesin (long haired) and soil-colored clothes (yellow, orange, saffron) engaged in the affairs of Mananat (mind, meditation). Rigveda, however, refers to these people as Muni and Vati. The Atharva Veda, completed by about 1000 BC, has more explicit discussion of Brahmacarya, in Book XI Chapter 5. This Chapter of Atharva Veda describes Brahmacarya as that which leads to one's second birth (mind, Self-awareness), with Hymn 11.5.3 painting a symbolic picture that when a teacher accepts a brahmacārī, the student becomes his embryo.
The concept and practice of Brahmacarya is extensively found among the older strata of the Mukhya Upanishads in Hinduism. The 8th century BC text Chandogya Upanishad describes in Book 8, activities and lifestyle that is Brahmacarya:
Now what people call yajña (sacrifice) is really Brahmacharya, for only by means of Brahmacharya does the knower attain that world (of Brahman). And what people call Ishta (worship) is really Brahmacharya, for only worshipping by means of Brahmacarya does one attain the Atman (the liberated Self). Now, what people call the Sattrayana (sacrificial session) is really Brahmacharya, for only by means of Brahmacharya does one obtain one's salvation from Sat (Being). And what people call the Mauna (vow of silence) is really Brahmacharya for only through Brahmacharya does one understand the Atman and then meditate. Now, what people call a Anasakayana (vow of fasting) is really Brahmacharya, for this Atman never perishes which one attains by means of Brahmacharya. And what people call the Aranyayana (life of a hermit) is really Brahmacharya, for the world of Brahman belongs to those who by means of Brahmacharya attain the seas Ara and Nya in the world of Brahman. For them there is freedom in all the worlds.
A hymn in another early Upanishad, the Mundaka Upanishad in Book 3, Chapter 1 similarly states,
सत्येन लभ्यस्तपसा ह्येष आत्मा सम्यग्ज्ञानेन ब्रह्मचर्येण नित्यम् । Through continuous pursuit of Satya (truthfulness), Tapas (perseverance, austerity), Samyajñāna (correct knowledge), and Brahmacarya, one attains Atman (the Self, soul).
The Vedas and early Upanishadic texts of Hinduism in their discussion of Brahmacarya, make no mention of the age of the student at the start of Brahmacarya, nor any restraint on sexual activity. One of the earliest discussion and contrasting viewpoints on sexual intercourse during Brahmacarya is in section 11.5.4 of Satpatha Brahamana. The verses 220.127.116.11 and 18.104.22.168 present two different viewpoints on sexual activity, one against and one as a choice. Similarly, in verse 22.214.171.124, the Satapatha Brahamana presents contrasting viewpoints on an eating restraint for the brahmacārī.
In ISKCON, a bhakti sect or devotional movement within Hinduism, a male devotee is called brahmacārī and female devotee brahmacārinī. The unmarried male brahmacārīs wear saffron robes, while married male householders wear white robes. Brahmacārinīs wear saris of any color. The terms brahmacārī and brahmacārinī are reserved for those practicing celibacy. Married devotees, in contrast, are called grihastha (householders).
Various Ashrams (आश्रम, hermitage) and Matha (मठ, college of ascetics) of various schools of Hinduism call their male and female initiates as brahmacārī and brahmacārinī.