The Church is one because of her source, the blessed Trinity--the unity of the Trinity of Persons of one God: the Father, Son, and Holy Spirit (#813; Cf. Vatican II, Unitatis redintegratio, 5).

The Church is one also because of her founder, the one Lord and savior, the only Son of God, the only name by which a man can be saved: Jesus the Christ (#813).

Likewise, the Church is one because of her soul, the form of the body of Christ, the life-giving principle: the Holy Spirit. The Holy Spirit brings about that unity which is of the very essence of the Church (#813). Although the Church is one and one only, there is a legitimate diversity within this one church. This is due to the variety of God's gifts and the great diversity of those who receive these gifts (#814). The many peoples, cultures, rites, and ways of prayer, rather than eroding unity, demonstrate the dynamic richness of the Church's oneness. The reality of sin, however, is always at work, and the unity that God intended for his Church is constantly threatened.

There are certain bonds of unity which hold the fabric of the Church together. First of all, as St. Paul teaches, there is charity, "which binds everything together in perfect harmony" (Col 3:14). In addition, the Catechism lists three visible bonds of communion which insure unity, if they are observed and maintained:

1. Profession of one faith which is received from the Apostles. Jesus Christ taught his Apostles the truth, which is God himself in essence. They then handed on this essential teaching in faith and morals to their successors: the bishops in union with the visible head of the Church, the successor of St. Peter, the pope. Remaining absolutely and uncompromisingly faithful to this one faith preserves the unity of the Church. Stepping outside of this one faith, rejecting any single tenet of this one faith sets in motion the forces of disunity--which is nothing less than a death wish, for the very principle of death is disunity. As things begin to break down, working out of harmony with each other, the life-giving forces of integrity fail and death holds sway.

2. Common celebration of divine worship, especially of the sacraments. The Church herself establishes her liturgical norms and rubrics, and although the legitimate differences in the various rites within the Catholic Church manifest the richness of her unity, the integrity of these rites themselves has to be maintained. Only the Church herself can establish her liturgical norms and rubrics. No individual has any authority to make essential changes in what the Church has laid down as her normative practice, whether in liturgy, doctrine or law. One should be able to just as easily recognize the celebration of the Eucharist in Peoria as Paris.

3. Apostolic succession through the sacrament of holy orders, maintaining the fraternal concord of God's family. Christ, the head of his Church, instituted his Church on the confession of faith of Peter. He grafted Simon the son of John into himself, making him one with the Rock--Christ himself; and, hence, he named him "Rock" or Peter. The sacrament of holy orders is of the essence for the Church. There can be no authentic church whatever without the successors of the Apostles; those who are ordained for their ministry through the sacrament of holy orders.

As the Catechism (#816) clearly teaches: "The sole Church of Christ [is that] which our Savior, after his Resurrection, entrusted to Peter's pastoral care, commissioning him and the other apostles to extend and rule it....This Church, constituted and organized as a society in the present world, subsists in the Catholic Church, which is governed by the successor of Peter and by the bishops in communion with him" (Vatican II, Lumen gentium, 8, 2).

The Second Vatican Council's Decree on Ecumenism explains: "For it is through Christ's Catholic Church alone, which is the universal help toward salvation, that the fullness of the means of salvation can be obtained. It was to the apostolic college alone, of which Peter is the head, that we believe that our Lord entrusted all the blessings of the New Covenant, in order to establish on earth the one Body of Christ into which all those should be fully incorporated who belong in any way to the People of God" (Vatican II, Unitatis redintegratio, 3, 5).

As we know, there have been wounds to this unity desired by Christ from the very beginning. Often enough, as the Church has taught, "men of both sides were to blame" (#817). In our time we cannot charge with the sin of heresy, apostasy, or schism those who are born into the various communities we have come to call "Protestant." The Catholic Church accepts our Protestant brothers and sisters with respect and affection (#818). As the Catechism reminds us, "All who have been justified by faith in Baptism are incorporated into Christ; they therefore have a right to be called Christians, and with good reason are accepted as brothers in the Lord by the children of the Catholic Church" (#818).

As true children of our heavenly Father we must long for and work towards that day when indeed there will be "one shepherd and one flock." The Church teaches us some very concrete ways by which we can work towards this much desired unity (#821). The first two constitute the heart of authentic ecumenism, and the only way the cause of unity will ever truly be furthered:

1."A permanent renewal of the Church in greater fidelity to her vocation." When we Catholics begin to live what we profess with intensity then others will be attracted to the Catholic Church. Spiritual tepidity, a mere "going through the motions" will never attract others to the Church. The word "lukewarm" is used once in all of Scripture. In the book of Revelation "The Amen", Jesus, in his message to the Church at Latakia says, "I know your deeds; I know you are neither hot nor cold. How I wish you were one or the other--hot or cold! But because you are lukewarm, neither hot nor cold, I will spew you out of my mouth!"

2."Conversion of heart as the faithful try to live holier lives according to the Gospel." The only way the Church will be all that she is called to be is by individual members of the Church becoming truly holy. Personal holiness is the answer and the only answer to all of the Church's problems, and the world's.

Great is the mystery of our faith, and great is both the mystery and the gift of the one church of Jesus Christ. May we pray constantly and work actively that indeed the longing of Christ's own heart may be fulfilled: that there might be once again one shepherd and one flock.