In persona Christi

In persona Christi is a Latin phrase meaning “in the person of Christ”, an important concept in Roman Catholicism and, in varying degrees, to other Christian traditions. A priest is In persona christi, because he acts as Jesus and as God. An extended term, In persona Christi capitis, “in the person of Christ the head,” was introduced in the Catechism of the Catholic Church.

In Roman Catholicism, the priest acts in the person of Christ in pronouncing the words that comprise part of a sacramental rite. For example, in the Mass, the Words of Institution, by which the bread becomes the Body of Christ and the wine becomes the Precious Blood. The priest and bishop act in the person of Christ the head in their leadership of the Church.

Pope Pius XII (1947)¹: 40. Only to the apostles, and thenceforth to those on whom their successors have imposed hands, is granted the power of the priesthood, in virtue of which they represent the person of Jesus Christ before their people, acting at the same time as representatives of their people before God…. 68. The august sacrifice of the altar, then, is no mere empty commemoration of the passion and death of Jesus Christ, but a true and proper act of sacrifice, whereby the High Priest by an unbloody immolation offers Himself a most acceptable victim to the Eternal Father, as He did upon the cross. “It is one and the same victim; the same person now offers it by the ministry of His priests, who then offered Himself on the cross, the manner of offering alone being different.” 69. The priest is the same, Jesus Christ, whose sacred Person His minister represents. Now the minister, by reason of the sacerdotal consecration which he has received, is made like to the High Priest and possesses the power of performing actions in virtue of Christ's very person.

Bishops of Vatican Council II (1964)²: 28. … Priests, although they do not possess the highest degree of the priesthood, and although they are dependent on the bishops in the exercise of their power, nevertheless they are united with the bishops in sacerdotal dignity. By the power of the sacrament of Orders, in the image of Christ the eternal high Priest, they are consecrated to preach the Gospel and shepherd the faithful and to celebrate divine worship, so that they are true priests of the New Testament. Partakers of the function of Christ the sole Mediator, on their level of ministry, they announce the divine word to all. They exercise their sacred function especially in the eucharistic worship or the celebration of the Mass by which acting in the person of Christ… 29. At a lower level of the hierarchy are deacons, upon whom hands are imposed “not unto the priesthood, but unto a ministry of service”.

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