Kātyāyana Śrautasūtra

Kalpa (Sanskrit: कल्प) means "proper, fit" and is one of the six disciplines of the Vedānga, or ancillary science connected with the Vedas – the scriptures of Hinduism. This field of study focussed on procedures and ceremonies associated with Vedic ritual practice.

The major texts of Kalpa Vedanga are called Kalpa Sutras in Hinduism. The scope of these texts included Vedic rituals, rites of passage rituals associated with major life events such as birth, wedding and death in family, as well as personal conduct and proper duties in the life of an individual. Most Kalpasutras texts have experienced interpolation, changes and consequent corruption over their history, and Apasthamba Kalpasutra ancillary to the Yajurveda may be the best preserved text in this genre.

Kalpa Sutras are also found in other Indian traditions such as Jainism.

Kalpa is a Sanskrit word that means "proper, fit, competent, sacred precept", and also refers to one of the six Vedanga fields of study. In Vedanga context, the German Indologist Max Muller translates it as "the Ceremonial".

The word is widely used in other contexts, such as "cosmic time" (one day for Brahma, 4.32 billion human years), as well as for precepts or procedures that are "proper, fit" in medicine or another profession.

The Kalpa field of study traces it roots to the Brahmana layer of texts in the Vedas, however its texts are more focussed, clear, short and practical for ceremonies. Kalpa Sutras are related to the Karma kanda or rituals parts of the Veda, in contrast to the Upanishads which are the Jnana kanda or the knowledge part.

This field of study emerged to serve the need of priests as they officiated over domestic ceremonies such as weddings and baby naming rites of passage, so that the rituals were efficient, standardized and appeared consistent across different events. They also helped the audience and the individuals integrate within customs and cultural practices, state Winternitz and Sarma, from "the moment when he is received in his mother's womb to the hour of his death", and beyond during his cremation.

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