In the earliest centuries of Christian public worship, psalms were generally sung by a solo voice, the congregation responding by repeating the final phrase or phrases of the chant. This was called the Psalmus Responsorius, or `Respond'. Towards the end of the fourth century another kind of psalmody was introduced, consisting of a psalm chanted by two groups alternately. The practice quickly spread (as if to demonstrate that people do, after all, like joining in when given the chance) and became known as Antiphonal psalmody. The whole psalm thus sung became known as the Antiphon; and the books in which the settings were inscribed were called Antiphonaries (or Antiphoners).
The meaning of the term has changed since then. In common speech the word `antiphon' has changed to `anthem', denoting a musical setting of almost any text and in almost any format. As a technical term, the word `antiphon' now generally refers to the device, similar to the original `Responds', in which a phrase taken from, or complementing, the words of a psalm or other text is sung (or spoken) by the congregation; leaving, once more, the main body of the psalm to be sung by a solo voice or small group of singers. The word Antiphon itself is then reserved for the response sung by the congregation.
In this form the practice has been common for many centuries of worship of all kinds; but it was given a new impetus and wide popularity through the psalmody developed by Joseph Gelineau and others. It has the great practical advantage that a congregation can quickly learn a short antiphon, with little or no musical experience, and thus participate in the singing or reading of a lengthy or complex psalm-setting.
In Rejoice & Sing, as elsewhere, the term Antiphon is used not only for the `Gelineau psalm' responses, but also for similar verses attached to psalms or canticles and set to `gregorian' psalm tones. Such settings can, of course, be equally well used for spoken reading as for singing.
(The Rejoice & Sing Enchiridion:edited by David Goodall; last amended 27/10/00)