Plenary council (Catholicism)

In the Roman Catholic Church, a plenary council is any of various kinds of ecclesiastical synods, used when those summoned represent the whole number of bishops of some given territory. The word itself, derived from the Latin plenarium (complete or full), hence concilium plenarium, also concilium plenum.

The ecumenical councils or synods are called plenary councils by Augustine of Hippo, as they form a complete representation of the entire Church. Thus also, in ecclesiastical documents, provincial councils are denominated plenary, because all the bishops of a certain ecclesiastical province were represented. Later usage has restricted the term plenary to those councils which are presided over by a delegate of the Apostolic See, who has received special power for that purpose, and which are attended by all the metropolitans and bishops of some commonwealth, empire, or kingdom, or by their duly accredited representatives. Such plenary synods are frequently called national councils.

Plenary councils, in the sense of national synods, are included under the term particular councils as opposed to universal councils. They are of the same nature as provincial councils, with the accidental difference that several ecclesiastical provinces are represented in national or plenary synods.

Provincial councils, strictly so-called, date from the fourth century, when the metropolitical authority had become fully developed. But synods, approaching nearer to the modern signification of a plenary council, are to be recognized in the synodical assemblies of bishops under primatial, exarchal, or patriarchal authority, recorded from the fourth and fifth centuries, and possibly earlier. Such were, apparently, the synods held in Asia Minor at Iconium and Synnada in the third century, concerning the re-baptism of heretics; such were, certainly, the councils held later in the northern part of Latin Africa, presided over by the Archbishop of Carthage, Primate of Africa. The latter councils were officially designated plenary councils (Concilium Plenarium totius Africae). Their beginnings are without doubt to be referred, at least, to the fourth, and possibly to the third century. Synods of a somewhat similar nature (though approaching nearer to the idea of a general council) were the Council of Arles in Gaul in 314 (at which were present the Bishops of London, York, and Caerleon), and the Council of Sardica in 343 (whose canons were frequently cited as Nicene canons). To these we might add the Greek Council in Trullo (692).

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