One Holy Catholic and Apostolic Church is a phrase in the Nicene Creed (μίαν αγίαν καθολικήν καί αποστολικήν Έκκλησίαν) that also appears partly in the Apostles Creed ("the holy catholic church"). It indicates the four marks of the Church – unity, holiness, catholicity and apostolicity – and is based on the premise that all true Christians (irrespective of race, nationality or sex) form a single united group, the body of Christ (cf. ), founded by the apostles and innately holy. While there is general agreement on the meaning of holy, and perhaps of one, the meanings of catholic and apostolic are debated.

Conflicting Catholic and Orthodox claims

The Catholic Communion, or Roman Catholic Church, comprising both the Western and the Eastern Rite Catholic particular Churches, claims that it is the One Holy Catholic and Apostolic Church. The Eastern Orthodox Church, comprising about 16 mutually recognizing autocephalous hierarchical Churches, similarly claims to be the One Holy Catholic and Apostolic Church. This disagreement has persisted since the Great Schism in the 11th century. Before that schism, the two were visibly united and claimed the title jointly.

Meaning of the word catholic

Etymologically, the word "catholic" comes from the Greek adjective katholikos (καθολικος) – καθολικήν is the accusative feminine singular form – formed on the basis of the adverb "katholou", which means "in general", "according to the whole". The word "catholic" thus means "general", "universal". In a religious context, especially if given an upper-case C, it distinguishes the faith or Church of the general body of Christians (as opposed to that of a separate distinct group) or at least that which is intended for people of every place and class. For the pre-Reformation Churches, at least, and thus for the majority of Christians, the word indicates acceptance of the fullness of the doctrine and practice of the historic Christian Church, including those parts that religious reformers rejected as contradicting what they held to be the true teaching of Christ.

The Roman Catholic Church, the Eastern Orthodox Churches, and the Oriental Orthodox Churches all see themselves as fully, and indeed exclusively, Catholic in all these senses. Anglicans of 'high church' or 'Anglo-Catholic' tradition consider themselves part of a "Catholic communion" not in submission to the Holy See of Rome, and maintain beliefs and practices akin to Catholicism, involving the sacraments and use of ritual in liturgy. Most other Protestants interpret "catholic" as meaning "for all people", and as referring to no institutional unity.

The Roman Catholic Church, the Eastern Orthodox Churches, and the Anglican Communion interpret the adjective apostolic as referring to unbroken and personal lineage (Apostolic Succession) from Christ’s apostles, transmitted by the laying on of hands in episcopal ordination. In their view, Christian communities that lack this mark are not Churches in the full sense. On the other hand, many Protestants and the majority of Anglicans hold that no one denomination embodies the apostolic Church of the Creed; rather that this Church is the aggregation of all Christians, encompassing multiple denominations, and that its full membership is known only to God – the doctrine of the "Church Invisible".

See also

• Creed
• History of Christianity
• Ecumenism