Holy Thursday marks the beginning of the sacred Easter Triduum, which concludes with the celebration of Easter Vigil Mass. On this day, we remember the Last Supper, during which “Jesus, loving those who were his own in the world even to the end, offered his Body and Blood to the Father under the appearance of bread and wine, gave them to the apostles to eat and drink, then enjoined the apostles and their successors in the priesthood to offer them in turn. This Mass is, first of all, the memorial of the institution of the Eucharist, that is, of the Memorial of the Lord’s Passover, by which under sacramental signs he perpetuated among us the sacrifice of the New Law. The Mass of the Lord’s Supper is also the memorial of the institution of the priesthood, by which Christ’s mission and sacrifice are perpetuated in the world” (Ceremonial of Bishops, 297).