A concise answer to this question is found in the fifth “Luminous Mystery” of the Rosary proposed by Pope John Paul II: “The institution of the Eucharist as the sacramental expression of the Paschal Mystery.”

At the Last Supper, the night before He died, offering Himself to the Father for our salvation, Jesus instituted the Eucharistic sacrifice of His body and blood in order to perpetuate or make present through the ages the self-sacrifice of His passion, death and resurrection. He entrusted this to His beloved spouse, the Church, through the Apostles and their successors who He commissioned to celebrate this memorial of His sacrificial death and resurrection as the source of the unity of the Church and the pledge of eternal life until He comes again in glory. {{read more}}

The Mass or the Eucharist as the sacramental representation or making present of the one sacrifice of Jesus is the ultimate act of thanksgiving to God the Father through the Incarnate Son in the Holy Spirit for all God’s works of creation, redemption and sanctification. Through the actions and the sacramental signs of the Eucharistic Liturgy the one sacrifice of Jesus is made present and its efficacy is applied for the salvation of all and the forgiveness of sins. Through the Mass, Jesus unites the Church His bride to His one self-offering to the Father in the Holy Spirit so that his sacrifice is also the sacrifice of the Church.

All the lives of the members of the Church, their praise, sufferings, prayers and works are united to those of Jesus and his total offering to the Father. The entire Church, those in the glory of heaven, the faithful departed not yet wholly purified – in purgatory – and all the faithful on earth are united by Jesus to His sacrifice in the action of the Mass.

In the Mass, through the action of those who share in the ministerial priesthood of Jesus passed on through Apostolic Succession, Jesus makes present His one sacrifice and unites to this all the members of his bride, the Church, who by active participation allow themselves to be taken up in His self-offering to the Father.

The offering of bread and wine commanded by the Lord Jesus as the sign or sacrament of His sacrifice is the means by which He is with us “always even until the end of time.” The bread and wine are substantially converted to His body and blood so that under the sacramental signs or species (appearances) that remain, Jesus is wholly present “body, blood, soul and spaninity.”

The real presence of Jesus under the Eucharistic species (appearances) of bread and wine begins with the consecration (words of institution of Jesus at the Last Supper) and continues as long as the Eucharistic species remain intact. The real presence of Jesus under the species of bread and wine are reverenced both during and after the celebration of the Mass by various acts of adoration such as genuflecting or bowing. The sacrament of the Eucharist is reserved in a secure place for the adoration of the faithful and to be taken to those who are unable to be present for the Mass.

The reception of the Lord’s body and blood brings the faithful into communion with the risen Lord and through Him into communion with the Father and the Holy Spirit. This communion brings about the communion and unity of the Church, which is then the sacrament or sign of the communion of the Trinity, Father, Son and Holy Spirit.

The one Holy, Catholic and Apostolic Church has her source and summit in the mystery of the Eucharist as the sacrifice of Jesus and the sacrament of His body and blood. At the same time the Eucharist is the pledge and sign of eternal life and “the new heavens and new earth.” The Mass is then the “sacred banquet in which Christ is received, the soul is filled with grace and a pledge of the life to come is given us.”

For more resources on the revised translation of the Roman Missal, visit the archdiocesan Office for Worship’s web site, http://archphila.org/Roman Missal/Roman Missal.html