"The Mass is at the same time, and inseparably, the sacrificial memorial in which the sacrifice of the cross is perpetuated and the sacred banquet of communion with the Lord's body and blood. But the celebration of the Eucharistic sacrifice is wholly directed toward the intimate union of the faithful with Christ through communion. To [...]
"We conclude this ecclesiological-Eucharistic catechesis by emphasizing that, if Eucharistic communion is the efficacious sign of unity, it then gives the faithful a continually new impulse to mutual love and reconciliation, and the sacramental strength necessary for preserving good understanding in family and ecclesial relationships." Source: Pope St. John Paul II, General Audience - [...]
"The Sacrament of the Eucharist is itself a striking and wonderful figure of the unity of the Church, if we consider how in the bread to be consecrated many grains go to form one whole, and that in it the very Author of supernatural grace is given to us, so that through Him we may [...]
"The refreshment of spiritual food and the unity denoted by the species of the bread and wine are to be had in the present life, although imperfectly, but perfectly in the state of glory. Hence Augustine says on the words, 'My flesh is meat indeed' (Jn. 6:56)." Source: St. Thomas Aquinas, Summa Theologica [...]
"The whole Church is united with the offering and intercession of Christ. Since he has the ministry of Peter in the Church, the Pope is associated with every celebration of the Eucharist, wherein he is named as the sign and servant of the unity of the universal Church. The bishop of the place is always [...]
"Faith means emerging from the isolation of one’s existence and becoming 'one body' with Christ, that is, existential unity with him. And this always means: existential unity of all who have become 'one body.'" Source: Pope Benedict XVI, Dogmatic Preaching: Applying Christian Doctrine to Daily Life, Ignatius Press, 2011.
"By means of the Eucharistic Sacrifice Christ our Lord willed to give the faithful a striking manifestation of our union among ourselves and with our divine Head, wonderful as it is and beyond all praise." Source: Pope Pius XII, MYSTICI CORPORIS CHRISTI, 6/29/1943. ENCYCLICAL OF POPE PIUS XII ON THE MISTICAL BODY OF CHRIST [...]
"Therefore in eucharistic Communion we receive Christ, Christ Himself; and our union with Him, which is a gift and grace for each individual, brings it about that in Him we are also associated in the unity of His body which is the Church." Source: Pope St. John Paul II, LETTER DOMINICAE CENAE OF THE [...]
"And so We earnestly hope that the restoration of the sacred liturgy will produce abundant fruits in the form of Eucharistic devotion, so that the Holy Church may, with this salvific sign of piety raised on high, make daily progress toward the full achievement of unity, inviting all Christians to a unity of faith and [...]
"The seeds of disunity, which daily experience shows to be so deeply rooted in humanity as a result of sin, are countered by the unifying power of the body of Christ." Source: Pope St. John Paul II, Papal Encyclical: Ecclesia De Eucharista, 4/17/2003