The Catholic Church traces its origins to Peter the Apostle.

Catholicism refers to the varying body of practices and beliefs unified in their general adherence to the doctrine of the Roman Catholic Church. Widely cited as the largest Christian affiliation in the world, the church has exercised considerable international influence from its inception to the present day. With such a large number of followers, The Catholic Church is reliant on a meticulous and complex hierarchy to disseminate the faith's traditions.


The Catholic Church holds that it is the one true church of God, tracing its roots to the foundation of the Roman Catholic Church by Peter the Apostle in the first century. Catholic doctrine refers to the text of the Bible, which is regarded as infallible, in claiming that Peter was given “the keys to the kingdom of heaven” (Matthew 16:18) and divine authority in his governance over his church and the followers of Christ. Each of Peter’s successors as head of the church, referred to as popes since the third century, are treated as an extension of this initial endowment of holy authority.

The Pope

Because of a pope’s apostolic connection to Peter, and thereby to Jesus Christ, he functions as the acting sovereign of the Catholic Church. The pope’s holy authority affords him papal primacy and infallibility -- his statements, decrees, and interpretations of scripture are the last word amongst all Catholic authority figures by divine right. This is exercised when he presides over the decisions of the governing officials of the Vatican. In addition, he performs all duties of an acting bishop and priest within his local territory.

Roman Curia

The Roman Curia is the administrative body by which the pope governs the Catholic Church. The Curia is comprised of many complex, interrelated offices that work toward the end of delegating official Catholic doctrine, promoting conversation within the church and increasing diplomatic relationships outside of the church. For example, the Congregation for the Doctrine of Faith investigates political, social and theological issues to determine the official canonical stance on a particular matter.

The Local Catholic Church

The organization of the church is also maintained territorially. The local church is presided over by an ordained priest. The priest is the acting head of his church and its surrounding territory, or parish. In addition to his governance, a Catholic priest performs the day-to-day tasks of interacting with local Catholics by managing church rituals. Non-ordained Catholic followers (referred to as the laity, or lay people), rely on priests for their absolution of sins through the sacraments of baptism and confession.

Dioceses, Bishops, and Archbishops

Parishes are grouped into local jurisdictions called dioceses. A bishop is a priest in a parish who is also the acting head of his local diocese. While there are over 200,000 parishes, there are only about 6,000 dioceses. In addition to performing the tasks of a priest, bishops work to deliver the directives of archbishops to other priests within their diocese. Archbishops function very similarly to bishops, except they preside over groups of dioceses rather than just one.