Custom. Any course of action that becomes habitual. The psychological effect of custom in every society is immense, not least in all forms of organized religion. People tend to become quickly "accustomed" to the way in which things have been done in the past and that they have come to find natural and congenial. They also tend to come to believe, as Montesquieu pointed out in his satire on his own French society (see Montesquieu, Charles de Secondat) that their own customs are or ought to be universal. Hume drew attention to the power of custom over thought, especially in his critique of the concepts of causation in traditional philosophy. In religious thought and practice, custom provides psychological solace and may have some beneficial effects, but it can stultify thought and inhibit the development of authentic religious experience. It is notorious that people often cling more tenaciously to comparatively recent customs than to ancient ones that may have more to commend them so long as one recognizes their consuetudinary nature. No where is this more patent than in organized religion. As every parish priest and pastor knows, it can be easier to persuade people to abandon a venerable liturgical practice that has proved its value throughout many centuries than to change a hymn tune.

Geddes MacGregor, Dictionary of Religion and Philosophy, New York: Paragon House, 1989

custom : (nt.) cāritta; vatta. (m.) āvāra; bali; rājakara.

A.P. Buddhadatta Mahathera, Concise Pali-English and English-Pali Dictionary [available as digital version from Metta Net, Sri Lanka]