As He was ascending to the glory of the Father, Jesus said: “Behold, I am with you always, until the end of the age” (Mt 28:20). And He also taught us: “Amen, amen, I say to you: unless you eat the flesh of the Son of Man and drink His blood, you do not have life within you” (John 6:53). He fulfills both of these promises by remaining with His Church and giving Himself to us in the Most Blessed Sacrament of the Holy Eucharist.
“The mode of Christ’s presence under the Eucharistic species is unique. It raises the Eucharist above all the sacraments as the perfection of the spiritual life and the end to which all the sacraments tend. In the Most Blessed Sacrament of the Eucharist the body and blood, together with the soul and divinity, of Our Lord Jesus Christ and, therefore, the whole Christ is truly, really, and substantially contained….It is by the conversion of the bread and wine into Christ’s body and blood that Christ becomes present in this sacrament…The Eucharistic presence of Christ begins at the moment of the consecration and endures as long as the Eucharistic species subsist. Christ is present whole and entire in each of the species and whole and entire in each of their parts, in such a way that the breaking of bread does not divide Christ.” (cf. CCC 1374, 1375, 1377)
“The Council of Trent summarizes the Catholic faith by declaring: ‘Because Christ our Redeemer said that it was truly His body that He was offering under the species of bread, it has always been the conviction of the Church of God, that this holy Council now declares again, that by the consecration of the bread and wine there takes place a change of the whole substance of the bread into the substance of the body of Christ our Lord and of the whole substance of the wine into the substance of His blood. This change the holy Catholic Church fittingly and properly calls transubstantiation.’” (CCC #1376)
In the Most Blessed Sacrament we behold the same Christ now worshiped in glory by the angels and saints: Come, let us adore Him!