The Eucharist, as stated in the Catechism of the Catholic Church, is “the source and summit of the Christian life.” All ecclesiastical ministries, all the Sacraments, and works of the apostolate, are bound up with the Eucharist and are oriented toward it. When the bread and wine are consecrated in the Eucharist, they cease to be simply the physical items bread and wine, and then become (respectively), the body and blood of Christ.
Empirically, the bread and wine both appear and feel no different physically. However, the greater reality of what they are has changed (a term you will often see written as transubstantiation). Consecration of the bread (known as the host) and wine represents the separation of Jesus’ body from his blood at Calvary. However, Christ has risen, and as such, the body and blood of Christ can no longer be truly separated. Where one is, so the other must be. Therefore, when the words, “The body of Christ”, when administering the host, and the words “The blood of Christ”, when presenting the chalice, the communicant who receives either one receives Christ, whole and entire.
The importance of this – the receipt of the entire Christ regardless if the body or blood is consumed – is important since individuals with aversions to gluten or fermented beverages can still receive the entire Eucharist by accepting either body or blood.
Because the Catholic Church was born of the paschal mystery, the Eucharist stands at the center of the life of Holy Mother Church. To wit, note that Acts 2:42 states “They devoted themselves to the Apostles’ teaching and fellowship, to the breaking of bread and the prayers” as one very clear indication of the importance of the Eucharist. Carrying on of this primordial image of the Catholic Church over the millenia is at every celebration of the Eucharist – for when we partake of the Sacrament of the Eucharist we are spiritually brought back to the paschal Triduum: literally to the events of the evening of Holy Thursday, to the Last Supper and all the glorious events that followed.
Thus, with the Baptism and the Confirmation, the Eucharist completes the Sacraments of Christian Initiation, and the beauty is that this is celebrated with every Mass.
By the Eucharistic celebration we already unite ourselves with the heavenly liturgy and anticipate eternal life, when God will be all in all.