The smṛtis and dharmaśāstras, the law books that regulate the life of individuals, both at the personal and at the social level, usually deal with three important topics: ācāra (ceremonial duties), vyavahāra (civil and criminal laws) and prāyaścitta (penances and expi-atory rites). Of the three, ācāra usually gets the pride of place. Literally, ācāra means conduct. It is often identified with sadācāra, the conduct of good and great men, so much so that dharma (righteousness) itself is said to be born out of ācāra, ‘ācāraprabhavo dharmaḥ’ (Mahābhārata, Anuśāsanaparva 161.172). Whenever one is in doubt with regard to one’s duty or action in a particular situation in life, one is advised to seek the guidance of the wise elders of impeccable character. Their words should be implicitly obeyed.
The ṣaṭkarmas, the six duties included under daily routine, are the most important aspects of ācāra at the personal level. They are: snāna (bath), sandhyā (the sandhyā ritual), japa (repetition of mantra), devapūjā (ritualistic worship of the family deity), homa (sacrifice), Vaiśvadeva (offerings of cooked food to all the gods) and ātithya (honouring the guests). Undergoing the various saṁskāras (purificatory rites) and performing the prescribed duties as per one’s varṇa (caste) and āśrama (stage of life) are the other important aspects of ācāra.
The word ācāra is also used in the sense of ‘customs and tradition’ which is equally important. No doubt the Vedas are the supreme authority in all matters regulating the Hindu society. Since they do not deal with the details of various problems that arise in the day-to-day life and conduct of the individuals, one has to rely upon the smṛtis (recorded collections of great sages) and sadācāra (the conduct of great men). However, in matters of dispute, falling within the jurisdiction of jurisprudence, ācāra as custom and long-standing tradition or usage, is often the decisive factor, provided it is not against the spirit of the Vedas and smṛtis. Such ācāra can be deśācāra (pertaining to the particular region), jātyācāra (pertaining to the particular caste) or kulācāra (pertaining to the particular family). Even the judges or the king had to take cognizance of these ācāras before giving their verdict.