Priests are at the height of their ministry when they celebrate the Eucharistic Sacrifice. Here they act in the name and person of Christ.
They alone consecrate bread and wine into the Body and Blood of Christ. They offer Christ to God the Father. The lay faithful, by the power of the common priesthood given by Baptism, offer with the priest and through him.
"For the common priesthood of the faithful and the ministerial or hierarchical priesthood, though they differ in essence and not only in degree, are ordered to one another, for both partake, each in its own way, of the one priesthood of Christ" (Lumen Gentium, 10; cf also Redemptionis Sacramentum, 36).