Youcat commented through CCC – Question n. 215.

YOUCAT Question n. 215 - Who leads the celebration of the Eucharist?

(Youcat answer) Actually Christ himself acts in every celebration of the Eucharist. The Bishop or the Priest represents him.

A deepening through CCC

(CCC 1140) It is the whole community, the Body of Christ united with its Head, that celebrates. "Liturgical services are not private functions but are celebrations of the Church which is 'the sacrament of unity', namely, the holy people united and organized under the authority of the bishops. Therefore, liturgical services pertain to the whole Body of the Church. They manifest it, and have effects upon it. But they touch individual members of the Church in different ways, depending on their orders, their role in the liturgical services, and their actual participation in them" (SC 26). For this reason, "rites which are meant to be celebrated in common, with the faithful present and actively participating, should as far as possible be celebrated in that way rather than by an individual and quasi-privately" (SC 27).

Reflecting and meditating 

(Youcat comment) It is the Church’s belief that the celebrant stands at the altar in persona Christi capitis (Latin = in the person of Christ, the Head). This means that priests do not merely act in Christ’s place or at his command; rather, on the basis of their ordination, Christ himself, as Head of the Church, acts through them.

(CCC Comment)

(CCC 1548) In the ecclesial service of the ordained minister, it is Christ himself who is present to his Church as Head of his Body, Shepherd of his flock, high priest of the redemptive sacrifice, Teacher of Truth. This is what the Church means by saying that the priest, by virtue of the sacrament of Holy Orders, acts in persona Christi Capitis (Cf. LG 10; 28; SC 33; CD 11; PO 2; 6): It is the same priest, Christ Jesus, whose sacred person his minister truly represents. Now the minister, by reason of the sacerdotal consecration which he has received, is truly made like to the high priest and possesses the authority to act in the power and place of the person of Christ himself (virtute ac persona ipsius Christi) (Pius XII, encyclical, Mediator Dei: AAS, 39 (1947) 548). Christ is the source of all priesthood: the priest of the old law was a figure of Christ, and the priest of the new law acts in the person of Christ (St. Thomas Aquinas, STh III, 22, 4c).   

(The next question is: In what way is Christ there when the Eucharist is celebrated?)