A Vedic student living in the house of the guru to learn the Vedas and allied sciences was called a ‘brahmacārin.’ He had to follow a given routine, observe a prescribed code of conduct and keep certain vows. Any violation of these vows, whether intentional or unintentional, had to be atoned by appropriate prāyaścittas or expiatory rites. Violation of the vow of brahmacarya or celibacy was the worst of these. The brahmacārin who wilfully had sexual intercourse with a woman was called an ‘avakīrṇin.’ The Dharmasūtras of Āpastamba (22.214.171.124) and Vasiṣṭha (23.1-3) as also the Manusmṛti (11.118-121) prescribe that the avakīrṇin should sacrifice an ass to the deity Nirṛti, which is symbolic of the stupid lapse, wear the skin of an ass for one year, should beg his food from seven houses announcing to them his lapse, take food only once in a day and bathe thrice a day. Then only he will become pure. Vasiṣṭha substitutes an oblation of boiled rice for the sacrifice of an ass.
See also BRAHMACĀRIN.