This is what the Church means by saying that the priest, by virtue of the sacrament of Holy Orders, acts in persona Christi Capitis [in the person of Christ, the Head]” (“Catechism of the ...
Q. 978. What is the Sacrament of Holy Orders? A. Holy Orders is a Sacrament by which bishops, priests, and other ministers of the Church are ordained and receive the power and grace to perform ...