Sacred time and sacred space are the categories by which religious traditions mark off portions of the temporal and spatial continuum as qualitatively different from the ordinary. The pairing was made central by Mircea Eliade in The Sacred and the Profane (1957), and much subsequent work has been a refinement of, or a reaction against, his account.
Eliade's argument is that for religious people space is not homogeneous. There are breaks in it, points where the sacred has manifested itself, which he called hierophanies, and these become centres around which a world is organised. Such a place is a fixed point in an otherwise undifferentiated expanse, is frequently identified with the centre of the world, and is where communication between the cosmic levels becomes possible. Time is likewise heterogeneous: festivals on his account are not commemorations but re-actualisations, entries into the primordial time of the events concerned, so that the sacred calendar periodically abolishes ordinary duration and renews the world.
The phenomena are real whatever one makes of the theory. Sacred spaces include temples, shrines, groves, mountains, rivers, tombs and thresholds, and they are characteristically marked by boundaries, entry requirements, purification, the removal of shoes, and rules about who may pass how far, the graded courts of the Jerusalem Temple and the enclosures of a Hindu temple being explicit spatial statements about who stands where. Sacred times include sabbaths, festivals, fasts, new years and the daily hours of prayer, and are typically marked by the suspension of ordinary work and by a different code of conduct.
Eliade's framework has been criticised extensively: for treating "archaic man" as a single type, for a normative preference for the religious over the secular that runs through work presented as descriptive, for inattention to history, and for presenting as universal a scheme assembled selectively. The most influential alternative is Jonathan Z. Smith's, in To Take Place (1987), which argues that sacredness is not a quality a place possesses but a position within a system of ritual attention, a place is sacred because of what is done there and how it is bounded, rather than being the site of a manifestation to which ritual afterwards responds. Smith's account has the advantage of explaining why sacred places can be made, moved and unmade, and why disputes over them prove so intractable: what is contested is the ordering of a system, not a property of the ground.
Contested sacred sites, Jerusalem's Temple Mount and Haram al-Sharif, Ayodhya, and many others, are where these theoretical questions acquire practical consequences, since incompatible ritual orderings of the same ground cannot both be enacted at once.