The Upanishads were composed during a time of much social, political, and economic upheaval. Rural tribal society was disappearing, and the adjustments of the people to urban living under a monarchy probably provoked many psychological and religious responses. During this period many groups of mystics, world renouncers, and forest dwellers appeared in India, among whom were the authors of the Upanishads. The most important practices and doctrines of these world renouncers included asceticism and the concept of rebirth, or transmigration.
The Rigveda contains few examples of asceticism, except among the “silent ones” (munis). The Atharvaveda describes another class of religious adepts, or specialists, the vratyas, particularly associated with the region of Magadha (west-central Bihar). The vratya was a wandering hierophant (one who manifested the holy) who remained outside the system of Vedic religion. He practiced flagellation and other forms of self-mortification and traveled from place to place in a bullock cart with an apprentice and with a woman who appears to have engaged in ritual prostitution. The Brahmans sought to bring the vratyas into the Vedic system by special conversion rituals, and it may be that the vratyas introduced their own beliefs and practices into Vedic religion. At the same time, the more-complex sacrifices of the later Vedic period demanded purificatory rituals, such as fasting and vigil, as part of the preparations for the ceremony. Thus, there was a growing tendency toward the mortification of the flesh.
The origin and development of the belief in transmigration of souls are very obscure. A few passages suggest that this doctrine was known even in the days of the Rigveda, and the Brahmanas often refer to doctrines of re-death and rebirth, but it was first clearly propounded in the earliest Upanishad—the Brihadaranyka. There it is stated that the soul of a Vedic sacrificer returns to earth and is reborn in human or animal form. This doctrine of samsara (reincarnation) is attributed to the sage Uddalaka Aruni, who is said to have learned it from a Kshatriya chief. In the same text, the doctrine of karma (“actions”), according to which the soul achieves a happy or unhappy rebirth according to its works in the previous life, occurs for the first time and is attributed to the theologian Yajnavalkya. Both doctrines seem to have been new, circulating among small groups of ascetics who were disinclined to make them public, perhaps for fear of the orthodox priests. These doctrines must have spread rapidly, for they appear in the later Upanishads and in the earliest Buddhist and Jain scriptures. Sutras, shastras, and smritis The Vedangas
Toward the end of the Vedic period, and more or less simultaneously with the production of the principal Upanishads, concise, technical, and usually aphoristic texts were composed about various subjects relating to the proper and timely performance of the Vedic sacrificial rituals. These were eventually labeled Vedangas (“Studies Accessory to the Veda”).
The preoccupation with the liturgy gave rise to scholarly disciplines, also called Vedangas, that were part of Vedic erudition. There were six such fields: (1) shiksa (instruction), which explains the proper articulation and pronunciation of the Vedic texts—different branches had different ways of pronouncing the texts, and these variations were recorded in pratishakhyas (literally, “instructions for the shakhas” [“branches”]), four of which are extant—(2) chandas (metre), of which there remains only one late representative, (3) vyakarana (analysis and derivation), in which the language is grammatically described—Panni’s grammar (c. 400 bce) and the pratishakhyas are the oldest examples of this discipline—(4) nirukta (lexicon), which discusses and defines difficult words, represented by the Nirukta of Yaska (c. 600 bce), (5) jyotisa (luminaries), a system of astronomy and astrology used to determine the right times for rituals, and (6) kalpa (mode of performance), which studies the correct ways of performing the ritual.
The texts constituting the Kalpa-sutras (collections of aphorisms on the mode of ritual performance) are of special importance. The composition of these texts was begun about 600 bce by Brahmans belonging to the ritual schools (shakhas), each of which was attached to a particular recension of one of the four Vedas. A complete Kalpa-sutra contains four principal components: (1) a Shrauta-sutra, which establishes the rules for performing the more complex rituals of the Vedic repertoire, (2) a Shulba-sutra, which shows how to make the geometric calculations necessary for the proper construction of the ritual arena, (3) a Grihya-sutra, which explains the rules for performing the domestic rites, including the life-cycle rituals (called the samskaras), and (4) a sutra" class="md-crosslink">Dharma-sutra, which provides the rules for the conduct of life.
Society was ritually stratified in the four classes, each of which had its own dharma (law). The ideal life was constructed through sacraments in the course of numerous ceremonies, performed by the upper classes, that carried the individual from conception to cremation in a series of complex rites. The Grihya-sutras show that in the popular religion of the time there were many minor deities who are rarely mentioned in the literature of the large-scale sacrifices but who were probably far more influential on the lives of most people than were the great Vedic gods. Dharma-sutras and Dharma-shastras
Among the texts inspired by the Vedas are the Dharma-sutras, or “manuals on dharma,” which contain rules of conduct and rites as they were practiced in various Vedic schools. Their principal contents address the duties of people at different stages of life, or ashramas (studenthood, householdership, retirement, and renunciation); dietary regulations; offenses and expiations; and the rights and duties of kings. They also discuss purification rites, funerary ceremonies, forms of hospitality, and daily oblations, and they even mention juridical matters. The most important of these texts are the sutras of Gautama, Baudhayana, and Apastamba. Although the direct relationship is not clear, the contents of these works were further elaborated in the more systematic Dharma-shastras, which in turn became the basis of Hindu law.
First among them stands the Dharma-shastra of Manu, also known as the Manu-smriti (Laws of Manu; c. 100 ce), with 2,694 stanzas divided into 12 chapters. It deals with topics such as cosmogony, the definition of dharma, the sacraments, initiation and Vedic study, the eight forms of marriage, hospitality and funerary rites, dietary laws, pollution and purification, rules for women and wives, royal law, juridical matters, pious donations, rites of reparation, the doctrine of karma, the soul, and punishment in hell. Law in the juridical sense is thus completely embedded in religious law and practice. The framework is provided by the model of the four-class society. The influence of the Dharma-shastra of Manu has been enormous, as it provided Hindu society with the basis for its practical morality. But, for most of the Indian subcontinent, it is the commentaries on it (such as Medhatithi’s 9th-century commentary on Manu) and, even more, the local case law traditions arising out of the commentaries that have been the law.
Second to Manu is the Dharma-shastra of Yajnavalkya; its 1,013 stanzas are distributed under the three headings of good conduct, law, and expiation. The Mitaksara, the commentary on it by Vijnaneshvara (11th century), has extended the influence of Yajnavalkya’s work. Smriti texts