The Eucharist is the center of our life. It is the source and summit of who we are as Catholics.
(National Directory for Catechesis, #35).
The Eucharist is not a sign or symbol of Jesus; rather we receive Jesus himself in and through the Eucharistic species. The priest, through the power of his ordination and the action of the Holy Spirit, transforms the bread and wine into the Body and Blood of Jesus. This is called transubstantiation.
By the consecration, the transubstantiation of the bread and wine into the Body and Blood of Christ is brought about. Under the consecrated species of bread and wine Christ himself, living and glorious, is present in a true, real, and substantial manner: his Body and his Blood, with his soul and his divinity. (CCC 1413).
Understanding the Mass
The central act of worship in the Catholic Church is the Mass. It is in the liturgy that the saving death and resurrection of Jesus once and for all is made present again in all its fullness and promise – and we are privileged to share in His Body and Blood, fulfilling his command as we proclaim his death and resurrection until He comes again. It is in the liturgy that our communal prayers unite us into the Body of Christ. It is in the liturgy that we most fully live out our Christian faith.
The liturgical celebration is divided into two parts: the Liturgy of the Word and the Liturgy of the Eucharist. First, we hear the Word of God proclaimed in the scriptures and respond by singing God’s own Word in the Psalm. Next, that Word is broken open in the homily. We respond by professing our faith publicly. Our communal prayers are offered for all the living and the dead in the Creed. Along with the Presider, we offer in our own way, the gifts of bread and wine and are given a share in the Body and Blood of the Lord, broken and poured out for us. We receive the Eucharist, Christ’s real and true presence, and we renew our commitment to Jesus. Finally, we are sent forth to proclaim the Good News!