What is “Church unity”? Probably the most shallow concept of church unity is in the ecumenical movement as popularly understood. “Church Unity” in this context means Christians of different denominations should meet together, be more charitable toward one another, find ways to work out their differences, and where possible, work together for the common good. That’s fine as far as it goes, and others would go further and say that we are all working toward eventual visible unity in some (as yet) unimagainable way.

Within the fullness of the Catholic faith church unity moves into a new dimension. When criticized for having over 20,000 different denominations, non-Catholics often point out that Catholics are ‘equally divided’ between liberals, conservatives etc. etc. etc. It is true that in the Catholic Church we do not have uniformity (nor should we desire uniformity) Instead we enjoy a kind of unity that transcends our individual opinions and human differences.

Apostolic letters from the Pope begin, “To all Patriarchs, archibishops, etc…in peace and communion with the Holy See.” They do not say, “to everyone who agrees with me in everything.” Instead the words “peace and communion” indicate profound theological concepts. Those who have preserved the “peace and communion” of the Body of Christ, are those who are able to make active submission to the Body of Christ through their submission to its physical and historical manifestation on earth: the Church. Their active and dynamic obedience places them in a relationship of peace and communion with the Holy See, and through that primary relationship of unity they enjoy a real relationship of peace and communion between themselves and all the faithful–even if that peace and communion are often strained by human failure, disagreements and strife.

That “peace and communion” is celebrated and made manifest in the ritual of Mass. It is celebrated and made manifest as we participate in the whole action of the Mass, and become one as we receive the Body and Blood of Christ, but it is also specified in the Kiss of Peace. This is why the Kiss of Peace should remain a formal liturgical act, and not just an opportunity to say “Good morning” and give everyone a hug and ask where they’re going to eat Sunday dinner. When we celebrate Christ’s peace we participate and affirm the profound reality of genuine peace and mutual charity that exists at the foundation of our shared faith.

The ‘communion’ of the whole church living and departed, and in all places and in all times is celebrated in another detail of the Mass. In the earliest days of the Church the presbyters who lived alone in the suburbs would not celebrate Mass on Sunday until the bishop had done so. At the bishop’s celebration, an acolyte would take a piece of the consecrated host and carry it to the outlying church where the presbyter would take the portion of the Body of Christ and place it in the chalice at his own celebration. Pope Innocent explained the practice thus: “So that the presbyters on this special day may not feel separated from our communion.”

This ancient practice survives today when the priest breaks the consecrated host, and immediately places a small part of it into the chalice. When he does so, he ritually recognizes that although we are separate from the whole body of Christ, by time, by geography, by death and sometimes by human disagreements and strife, still there is an underlying unity in the Body of Christ.

What is vital to remember is that the more we, as individuals, submit to the simple teachings of the church, the more we grow together in unity. The more we push our own agendas, disagree, pick fights with others and ‘un-church’ others, the more we sin against unity, and in so doing, sin against the Body of Christ.

These thoughts are gleaned from my reading of Mgr. Guissani’s The Journey to the Truth is an Experience.