Vicarius principis apostolorum

Vicar of Christ (from Latin Vicarius Christi) is the term used in different ways, with different theological connotations throughout history. As the original notion a vicar is of "earthly representative of Christ" but also used in sense of "person acting as parish priest in place of a real person" The title is now used in Catholicism to refer to the bishops and more specifically to the Bishop of Rome (the pope).

During the history of Christianity, the title of Vicar of Christ was used in different ways, with implications for theological, pastoral or different time.

The first record of the concept of the Vicar of Christ is mentioned in the Epistle to the Magnesians of St. Ignatius, Bishop of Antioch, who was possibly a disciple of both John the Apostle and Saint Peter, with a pastoral sense, written between the years 88 and 107 AD "your bishop presides in the place of God (...)". Although Ignatius did not explicitly use the term Vicar of Christ, he clearly sets out the concept. More recently, the Second Vatican Council's Dogmatic Constitution on the Church Lumen gentium noted that bishops are "vicars and ambassadors of Christ," and the Catechism of the Catholic Church notes that each bishop governs his diocese "[a]s Christ's vicar."

The second recorded use of the term "Vicar of Christ" is found in the epistles of Tertullian in the 3rd century, with a different theological slant to refer to the Holy Spirit, that is, as Christ is not physically performing miracles in the Church, Holy Spirit acts as his Vicar on his behalf, performing miracles and preventing the Church err. It is unknown whether this term was widely used in the early Church, or whether it was a personal theological observation of Tertullian.

The third use of the term Vicar of Christ appears in the 5th century, in a synod of bishops to refer to Pope Gelasius I. The theological connotations of the title got a pastoral sense, evoking the words of Christ to the Apostle Peter, regarded by the first Catholic Pope in John 21:16-17, "Feed my lambs... Feed my sheep", so Christ made Peter his vicar and pastor with the responsibility to feed his flock (i.e. the Church) in his own place.

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