Catholicism has two main ecclesiastical meanings, described in Webster's Dictionary as: a) "the whole orthodox Christian church, or adherence thereto"; and b) "the doctrines or faith of the Roman Catholic church, or adherence thereto." 1
The term comes from the Greek adjective καθολικ?ς -? -?ν (katholikos), meaning "general" or "universal".
Although most Christian denominations affirm faith in "One Holy Catholic and Apostolic Church", the term Catholicism as widely understood applies to the Catholic Church, governed by the Bishop of Rome and the bishops in communion with him.
However, other Churches that trace their historic episcopate to the apostolic succession — such as the Oriental Orthodox Churches, the Eastern Orthodox Churches, the Assyrian Church of the East, the churches of the Anglican Communion, and the Old-Catholics — consider themselves simply to be different, non-Roman, branches or Communions of the Catholic Church. Neo-Lutheranism argues that Lutheran Churches are simply a Protestant reform movement that remains within the greater Church catholic.

The term "Catholic Church"

A letter that, in about 107, Saint Ignatius, Bishop of Antioch wrote to Christians in Smyrna, is the earliest surviving witness to the use of the term "catholic Church" (Smyrnaeans, 8).[1] By it Saint Ignatius designated the Christian Church in its universal aspect, excluding heretics, such as those who disavow "the Eucharist to be the flesh of our Saviour Jesus Christ, which suffered for our sins, and which the Father, of His goodness, raised up again" (Smyrnaeans, 7).[2] He called such people "beasts in the shape of men, whom you must not only not receive, but, if it be possible, not even meet with" (Smyrnaeans, 4).[3]
Yet more explicit was the manner in which Saint Cyril of Jerusalem (circa 315-386) used the term "catholic Church" precisely to distinguish this Church from heretical "Churches". He urged: "If ever thou art sojourning in cities, inquire not simply where the Lord's House is (for the other sects of the profane also attempt to call their own dens houses of the Lord), nor merely where the Church is, but where is the Catholic Church. For this is the peculiar name of this Holy Church, the mother of us all, which is the spouse of our Lord Jesus Christ, the Only-begotten Son of God" (Catechetical Lectures, XVIII, 26).[4]
Only slightly later, when Christians still applied the word "priest" only to bishops and not yet to those who are now called "priests" in English, Saint Augustine of Hippo (354-430) wrote:

"In the Catholic Church, there are many other things which most justly keep me in her bosom. The consent of peoples and nations keeps me in the Church; so does her authority, inaugurated by miracles, nourished by hope, enlarged by love, established by age. The succession of priests keeps me, beginning from the very seat of the Apostle Peter, to whom the Lord, after His resurrection, gave it in charge to feed His sheep (Jn 21:15-19), down to the present episcopate.
"And so, lastly, does the very name of Catholic, which, not without reason, amid so many heresies, the Church has thus retained; so that, though all heretics wish to be called Catholics, yet when a stranger asks where the Catholic Church meets, no heretic will venture to point to his own chapel or house.
"Such then in number and importance are the precious ties belonging to the Christian name which keep a believer in the Catholic Church, as it is right they should ... With you, where there is none of these things to attract or keep me... No one shall move me from the faith which binds my mind with ties so many and so strong to the Christian religion... For my part, I should not believe the gospel except as moved by the authority of the Catholic Church."
— St. Augustine (354–430): Against the Epistle of Manichaeus called Fundamental, chapter 4: Proofs of the Catholic Faith[5]

A contemporary of Augustine, St. Vincent of Lerins, wrote in 434 under the pseudonym Peregrinus a work known as the Commonitoria ("Memoranda"). While insisting that, like the human body, Church doctrine develops while truly keeping its identity (sections 54-59, chapter XXIII), he stated: "[I]n the Catholic Church itself, all possible care must be taken, that we hold that faith which has been believed everywhere, always, by all. For that is truly and in the strictest sense 'Catholic,' which, as the name itself and the reason of the thing declare, comprehends all universally. This rule we shall observe if we follow universality, antiquity, consent. We shall follow universality if we confess that one faith to be true, which the whole Church throughout the world confesses; antiquity, if we in no wise depart from those interpretations which it is manifest were notoriously held by our holy ancestors and fathers; consent, in like manner, if in antiquity itself we adhere to the consentient definitions and determinations of all, or at the least of almost all priests and doctors" (section 6, end of chapter II).
The word Catholic has been used ever since to describe the genuine one original Church founded by Christ and the Apostles. The word appears in the main Christian creeds (formal definitions of belief), notably the Apostles' Creed and the Nicene Creed.

Divergent interpretations of the term "Catholic Church"

Many Christians (and denominations) see themselves as "catholic". They fall into two groups:
1) those like the Roman Catholic, Eastern Orthodox, Oriental Orthodox, and Anglican Churches having Apostolic Succession from the early Church; and
2) those who claim to be spiritual descendants of the Apostles but have no discernable institutional descent from the historic Church, and normally do not refer to themselves as catholic.
Christians of most denominations, including most Protestants, affirm their faith in "One Holy Catholic and Apostolic Church". For Protestants, most of whom consider themselves to be spiritual descendants (category 2, above), this affirmation refers to their belief in the ultimate unity of all Churches under one God and one Saviour, rather than in one visibly unified institutional Church (category 1, above). In this usage catholic is sometimes written with a lower-case "c". The Western Apostles' Creed, stating "I believe in...the holy catholic church..." (sometimes capitalised), is thus recited in Protestant worship services (with the notable exception of German Lutherans, who substitute "Christian" for "catholic"). The Nicene Creed likewise declares belief in "one, holy, catholic and apostolic Church". It should be noted historically, however, that apostolicity in the form of tactile succession as well as spiritual descent has been maintained by certain national Lutheran Churches (now part of the Porvoo Communion), and has been restored in this fully visible form to the Evangelical Lutheran Church in Canada and the Evangelical Lutheran Church in America through the procedures of full communion agreements with their national Anglican counterparts.

Brief organizational history of the Church

The early Catholic Church came to be organized under the three patriarchs of Rome, Alexandria and Antioch, to which later were added the patriarchs of Constantinople and Jerusalem. The Bishop of Rome was at that time recognized as first among them, as is stated, for instance, in canon 3 of the First Council of Constantinople (381) - many interpret "first" as meaning here first among equals - and doctrinal or procedural disputes were oftentimes referred to Rome, as when, on appeal by St Athanasius against the decision of the Council of Tyre (335), Pope Julius I, who spoke of such appeals as customary, annulled the action of that council and restored Athanasius and Marcellus of Ancyra to their sees. The Bishop of Rome was also considered to have the right to convene ecumenical councils. When the Imperial capital moved to Constantinople, Rome's influence was sometimes challenged. Nonetheless, Rome claimed special authority because of its connection to Saint Peter2 and Saint Paul, who, all agreed, were martyred and buried in Rome, and because the bishop of Rome saw himself the direct successor of Saint Peter.
The 431 Council of Ephesus, the Third Ecumenical Council, was chiefly concerned with Nestorianism, which emphasized the distinction between the humanity and divinity of Jesus and taught that, in giving birth to Jesus Christ, the Virgin Mary could not be spoken of as giving birth to God. This Council rejected Nestorianism and affirmed that, as humanity and divinity are inseparable in the one person of Jesus Christ, his mother, the Virgin Mary, is thus Theotokos, God-bearer, Mother of God. The first great rupture in the Church followed this Council. Those who refused to accept the Council's ruling were largely Persian and are represented today by the Assyrian Church of the East and related Churches, which, however, do not now hold a "Nestorian" theology. They are often called Ancient Oriental Churches.
The next major break was after the Council of Chalcedon (451). This Council repudiated Eutychian Monophysitism which stated that the divine nature completely subsumed the human nature in Christ. This Council declared that Christ, though one person, exhibited two natures "without confusion, without change, without division, without separation" and thus is both fully God and fully human. The Alexandrian Church rejected the terms adopted by this Council, and the Christian Churches that follow the tradition of non-acceptance of the Council - they are not Monophysite in doctrine - are referred to as Pre-Chalcedonian or Oriental Orthodox Churches.
The next great rift within Christianity was in the 11th century. Doctrinal disputes, as well as conflicts between methods of Church government, and the evolution of separate rites and practices, precipitated a split in 1054 that divided the Church, this time between a "West" and an "East". England, France, the Holy Roman Empire, Scandinavia, and Western Europe in general were in the Western camp, and Greece, Romania, Russia and many of other Slavic lands, Anatolia, and the Christians in Syria and Egypt who accepted the Council of Chalcedon made up the Eastern camp. This division is called the East-West Schism.
The fourth major division in the Church occurred in the 16th century with the Protestant Reformation, after which many parts of the Western Church either entirely rejected the teachings of the Roman Catholic Church and became known as "Reformed" or "Protestant", or else repudiated Roman papal authority and accepted decisions by the civil ruler in religious matters.
A much less extensive rupture occurred when, after the Roman Catholic Church's First Vatican Council, in which it officially proclaimed the dogma of papal infallibility, clusters of Catholics in the Netherlands and in German-speaking countries formed the Old-Catholic (Altkatholische) Church and other Independent Catholic Churches.
All of the preceding groups, excluding some Protestants, consider themselves fully and completely Catholic, either as part of the Catholic Church or as the one and only Catholic Church.

The Roman Catholic Church

"The Catholic Church", when used not of an abstract invisible entity, but of a visible concrete body of Christians, usually refers to what is also called "the Roman Catholic Church".
This Church does not often use the name "Roman Catholic Church" for itself, except in its relations with other Christian groups. Even in those relations, "Catholic Church" may also appear, as in some documents drawn up in common with the Lutheran World Federation and the Assyrian Church of the East. On the other hand, the Church has in fact applied the adjective "Roman" to itself in its entirety even in some internal documents, such as the Dogmatic Constitution de fide catholica of the First Vatican Council, which was attended by Eastern as well as Western bishops. When it does apply the adjective "Roman" to itself, it understands this word only as pointing to the centrality for it of the see of Rome, with which all its members, laity and clergy alike, are necessarily in full communion. Outsiders, in contrast, considering the use of the name "Catholic Church" by this Church to be contentious, use the term "Roman Catholic Church" to imply that it is only the "Roman" section of some larger, perhaps abstract, entity that they call the Catholic Church and that, in their view, also includes other sections not in communion with Rome, a usage that members of the Church in question in turn see as contentious.

Frequently enough, some members of this Church, especially those of Eastern Rite, apply the term "Roman Catholic Church" not, as in the Church's official documents, to the Church as a whole, but only to its Latin Rite component. Unlike the outsiders just mentioned, these consider communion with the see of Rome essential for all members of the Catholic Church.

Other Catholics

In Western Christianity the principal groups that regard themselves as "Catholic" without full communion with the Pope are the Chinese Patriotic Catholic Association and some elements of Anglicanism ("High Church Anglicans" or "Anglo-Catholics"). Smaller groups include the Old Catholics, the Aglipayans (Philippine Independent Church), and the Polish National Catholic Church of America. Their spiritual beliefs and practices are similar to those of Catholics of the Latin Rite, from which they emerged, but they reject the Pope's claimed status and authority.

The Anglican Communion is in practice divided into two wings of unequal size, "High Church Anglicans", also called the Anglo-Catholics, said to be the great majority in most Anglican/Episcopal Churches, and "Low Church Anglicans", also known as the Evangelical wing. Though all elements within the Anglican Communion recite the same creeds, Low Church Anglicans regard the word Catholic in the ideal sense given above, while High Church Anglicans treat it as a name of an identifiable Church which they consider to embrace themselves together with the Catholic, Old-Catholic, Lutheran and several Eastern Churches.
Anglo-Catholicism has no official fixed tenets, other than rejection of Roman "Ultramontanism," but maintains similarities to both Roman Catholicism and Eastern/Oriental Orthodoxy, as well as to related spirituality, including a belief in seven sacraments, devotion to the Virgin Mary and saints, and emphasize the description of their ordained clergy as "priests", addressed as "Father"(or, in the case of women priests, "Mother"). They have re-emphasized the wearing of vestments and the use of candles and incense and other ceremonial elements in church liturgy, sometimes describing their Eucharistic celebrations with the Latin-derived word "Mass". Some Anglo-Catholics believe in Transubstantiation, as opposed to Consubstantiation, or in other ideas of metousiosis or Real Presence. The development of the Anglo-Catholic wing as a distinct party occurred largely in the nineteenth century, and is strongly associated with the Oxford Movement. Two of its leading lights, John Henry Newman and Henry Edward Manning, both ordained Anglican priests, ended up joining the Catholic Church, becoming cardinals. The parallel "party" among Lutherans, High Church Lutheranism, developed a movement known as Neo-Lutheranism.

The Eastern Orthodox and Oriental Orthodox Churches, as well as the Assyrian Church of the East, each consider themselves to be the universal and true Catholic Church. In various permutations, these bodies typically regard other and Western Catholics as heretical and as having thus left the One, Holy, Catholic, and Apostolic Church. The patriarchs of these Eastern Orthodox and Oriental Orthodox Churches are autocephalous hierarchs, which roughly means that each is independent of the direct oversight of another bishop, although still subject, according to their distinct traditions, either to the synod of bishops of each one’s jurisdiction, or only to a common decision of the patriarchs of their own communion. They are willing to concede a primacy of honor to the Roman See, but not of authority, nor do they accept its claim to universal and immediate jurisdiction. This is similar to the position taken by the Lutheran World Federation, the Anglican Communion, and the Old Catholic Church.

Distinctive Beliefs and Practices

Catholic Churches share certain essential distinctive beliefs and practices (though some Anglicans and Lutherans differ in regard to emphasis and particular pieties):

• Direct and continuous organizational descent from the original church founded by Jesus (see e.g. Mt 16:18).
• Possession of the "threefold ordained ministry" of Bishops, Priests and Deacons.
• All ministers are ordained by, and subject to, Bishops, who pass down sacramental authority by the "laying-on of hands", having themselves been ordained in a direct line of succession from the Apostles (see Apostolic Succession).
• Their belief that the Church is the vessel and deposit of the fullness of the teachings of Jesus and the Apostles from which the Scriptures were formed. This teaching is preserved in both written Scripture and in unwritten Tradition, neither being independent of the other.
• A belief in the necessity of sacraments (generally counted as seven).
• The use of sacred images, candles, vestments and music, and often incense and water, in worship.
• Belief that the Eucharist is really, truly, and objectively the Body and Blood of Christ, through the Real Presence. Those that are quite distinctively Catholic believe that adoration and worship is due to the Eucharist, as the body and blood of Christ.
• Veneration of Mary, the mother of Jesus as the Blessed Virgin Mary or Theotokos, and veneration of the saints.
• A distinction between adoration (latria) for God, and veneration (dulia) for saints. The term hyperdulia is used for a special veneration accorded to the Virgin Mary among the saints. Some do not accept the distinction between hyperdulia and dulia.
• The use of prayer for the dead.
• Requests to the departed saints for intercessory prayers.
• Belief in Exorcisms

Sacraments or Sacred Mysteries

Catholics administer seven sacraments or "sacred mysteries", traditionally listed in the following order (cf. Catechism of the Catholic Church):

• Baptism
• Confirmation, also called Chrismation
• Eucharist
• Reconciliation of a Penitent
• Anointing of the Sick
• Holy Orders
• Holy Matrimony also known as "Marriage"

While the word mystery is used not only of these rites, but also with other meanings with reference to revelations of and about God and to God's mystical interaction with creation, the word sacrament (Latin: a solemn pledge), the usual term in the West, refers specifically to these rites.

Baptism is the first sacrament of Christian initiation, the basis for all the other sacraments. Catholics consider baptism conferred in most Christian denominations "in the name of the Father, and of the Son, and of the Holy Spirit" (cf. Matthew 28:19) to be valid, since the effect is produced through the sacrament, independently of the faith of the minister, though not of the minister's intention. As stated in the Nicene Creed, Baptism is "for the remission of sins", not only personal sins, but also of original sin, which it remits even in infants who have committed no actual sins. Expressed positively, remission of sins means bestowal of the sanctifying grace by which the baptized person shares the life of God. The initiate "puts on Christ" (Galatians 3:27), and is "buried with him in baptism ... also raised with him through faith in the working of God" (Colossians 2:12).

Confirmation or Chrismation is the second sacrament of Christian initiation. Through it, the gift of the Holy Spirit conferred in baptism is "strengthened and deepened" (see Catechism of the Catholic Church, §1303) by a sealing. Some theologies consider this to be the outward sign of the inner "Baptism of the Holy Spirit," the special gifts (or charismata) of which may remain latent or become manifest over time according to God's will. Its "originating" minister is a validly consecrated bishop; if a priest (a "presbyter") confers the sacrament - as is done ordinarily in Eastern, Anglican, and Lutheran Churches and in particular cases in the Latin Rite of the Roman Catholic Church - the link with the higher order is indicated by the use of chrism (also called myrrh) blessed by a bishop (in an Eastern Orthodox Church, by the patriarch). In the East, and among Anglicans and Lutherans, the sacrament is administered immediately after baptism. In the West administration came to be postponed until the recipient's early adulthood; but in view of the earlier age at which children are now admitted to reception of the Eucharist, it is more and more restored in the Roman Catholic Church to the traditional order and administered before giving the third sacrament of Christian initiation. In the Lutheran and Anglican traditions, "Confirmation" has come to be seen as a mature expression of faith, graced by the laying-on of a bishop's hands, and separated as a rite from the actual conferring of the chrismation.

The Eucharist is the sacrament (the third of Christian initiation) by which, according to Catholic doctrine, Catholics receive their ultimate "daily bread," or "bread for the journey," by partaking of and in the Body and Blood of Jesus Christ and being participants in Christ's one eternal sacrifice. The bread and wine used in the rite are, according to Catholic faith, in the mystical action of the Holy Spirit, transformed to be objectively Christ's Body and Blood, his Real Presence. This transformation is suggested through the concept of metousiosis in the East and in several Western Churches. The Roman Catholic Church has officially adopted the philosophical formula of transubstantiation to describe the change in the elements (the bread and wine).

The Reconciliation of a Penitent (or, simply, Reconciliation), Penance and Confession are names given to the first of the two sacraments of healing. It is also called the sacrament of conversion, of forgiveness, and of absolution (Catechism of the Catholic Church, 1423-1424).[6] It is the sacrament of spiritual healing of a baptized person from the distancing from God involved in actual sins committed. It involves four elements: the penitent's contrition for sin (without which the rite does not have its effect), confession to a priest (it may be spiritually helpful to confess to another and doing such is actually encouraged within the Church, but only a priest has the power to administer absolution), absolution by the priest, and satisfaction (signs of repentance that help the penitent's growth). In early Christian centuries, the fourth element was quite onerous and generally preceded absolution, but now it usually involves a simple task (in some traditions called a "penance") for the penitent to perform, to make some reparation and as a medicinal means of strengthening against further sinning.
Anointing of the Sick (or Unction) is the second sacrament of healing. In it those who are suffering a serious illness are anointed by a priest with oil blessed specifically for that purpose. "Seriously sick" does not necessarily mean "in immediate danger of death". In past centuries, when such a restrictive interpretation was customary, the sacrament came to be known as "Extreme Unction", i.e. "Final Anointing", as it still is among traditionalist Catholics. It was then conferred only as one of the "Last Rites". The other "Last Rites" are Confession (if the dying person is physically unable to confess, at least absolution, conditional on the existence of contrition, is given), and the Eucharist, which, when administered to the dying, is known as "Viaticum", a word whose original meaning in Latin was "provision for a journey". Since the advent of the AIDS crisis, the conferring of Anointing of the Sick has become customary at Communion-time in many urban Anglican and Lutheran parishes.

The Sacrament of Order is that which integrates men (and in some jurisdictions, also women) into the Holy Orders of bishops, priests (presbyters), and deacons, the threefold order of "administrators of the mysteries of God" (1 Corinthians 4:1), giving the person the mission to teach, sanctify, and govern, the three functions referred to in Latin as the "tria munera". Only a bishop may administer this sacrament, as only a bishop holds the fullness of the Apostolic Ministry. Ordination as a bishop makes one a member of the body that has succeeded to that of the Apostles. Ordination as a priest configures a person to Christ the Head of the Church and the one essential Priest, empowering that person, as the bishops' assistant and vicar, to preside at the celebration of divine worship, and in particular to confect the sacrament of the Eucharist, acting "in persona Christi" (in the person of Christ). Ordination as a deacon configures the person to Christ the Servant of All, placing the deacon at the service of the Church, especially in the fields of the ministry of the Word, service in divine worship, pastoral guidance and charity.

Marriage (or Holy Matrimony) joins two persons for mutual help and love (the unitive purpose), consecrating them for their particular mission of building up the Church and the world, and providing grace for accomplishing that mission. In Roman Catholic theology, the primary purpose of marriage seen as the bearing and raising children (the procreative purpose), and marriage may only be between one man and one woman. Western tradition sees the sacrament as conferred by the canonically expressed mutual consent of the partners in marriage; Eastern and some recent Western theologies not in communion with the see of Rome view the blessing by a priest as constituting the sacramental action.

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