The Old Catholic Churches of the Union of Utrecht are connected to the Early Church through its understanding and definition of what the church is. That is to say, Old Catholics share an understanding of the church's nature that is in solidarity with how the Early Church, generally speaking, understood the essence of church to be. Old Catholics attempt to live in continuity with the teaching principles of the Church Catholic of the first millennium. Ploeger states it best when interpreting Küry's assertion that Old Catholics strive to live in continuity with the undivided Early Church by explaining it is "a [intentional] return to the principle decisions of the Early Church...a return to the major issues of Scripture, creed and ministry, rather than remaining within the historic divisions and its many denominational confessions, which date from the second millennium (Ploeger, "Celebrating Church: Ecumenical Contributions to a Liturgical Ecclesiology" (Universiteit van Tilburg, 2008), 191)."
The local-universal Church cannot be foundationally viewed as a corporation, non-profit agency, and/or charitable center, but is rather the local Body of Christ comprised of living human persons: the baptized! Put another way, the church is the gathering of the local baptized around their bishop in the liturgical celebration of Holy Eucharist: the Mass. The church then for Old Catholics is essentially local, organic, and relational by nature. Now, many western Christians and Christian denominations openly acknowledge this assertion of the church's nature as though this idea is a common experience most baptized persons encounter today...as though it is an essential fact of how people today understand the essence of the church a priori. I disagree with this assumption and find such arguments a bit audacious because it ignores the fact that most baptized persons (lay and ordained) do not commonly view the church's nature as being primarily organic, but rather as institutional, hierarchical, and confessional/denominational.
The church, it seems, is everything but organic to most in the U.S.--of course many acknowledge the primary organic nature of the church, but the question to be asked is along the lines of whether one truly believes in one's heart that s/he manifests with the other baptized the local Church Catholic, that they have an "ecclesial" identity which is Christ's identity by virtue of their baptism into his life, death, and resurrection. Are the hearts of the local baptized truly transformed to that of Christ's paschal mystery, which is centered in the energy of the Spirit, or is such "missional" discourse about "being the church" merely political and ideological rhetoric of liberal, conservative, monarchical, or democratic factions? A church primarily seen as institutional and a power separate from the local baptized is not the church, but more of a human instrument of trying to contain something that cannot be contained: the Holy Spirit.
The question I pose above indeed needs further pondering because it is one thing to say the church is the people, and another reality altogether when the people realize in their hearts that they indeed are the church, that they are the primary essence and identity of what constitutes "ecclesia". There needs to happen in our day a rekindling of the question posed long ago by the men walking on the road to Emmaus after they encountered the Christ: "Were not our hearts burning within us while he was talking to us on the road, while he was opening the scriptures to us (Lk 24:32)?" Old Catholicism inspires and seriously contemplates this rich tradition of the Early Church where the local baptized know with hearts aflame that they are the ones who constitute and "concretize" in history the one, holy, catholic, and apostolic church of the ages. Of course the institution of the local-universal church is a reality, however, my assertion here is that it is a secondary reality and cannot, never will, exude the primary nature of the church as the local Body of Christ: organic and energized by the Spirit.
Every parish I visited, whether it be in Germany or in Prague, was small in size (less than 300 members). There could be many reasons for their smallness, but I believe it is due to the reality of how Old Catholics understand the nature of the church as being primarily identified with the local baptized in relation to each other and their bishop. One cannot be relational in a "mega-church" or a church community that totals in the thousands, at least not in any meaningful way. No, the Old Catholic communities in Europe tend to be small in size because they are relational...the community wants to know its members and really be the Body of Christ together in a meaningful way. For example, I learned that the Old Catholic parish I visited in Stuttgart, Germany requests a person and/or family to journey with the parish for 6 months to a year before petitioning the parish council to become a member. This policy is not exclusionary by nature, nor is it meant to be oppressive. It is rather a way for the person/family to get to know the parish community and vice-versa...to really establish a meaningful relationship with each other in celebration of all that is the liturgical essence of living the eucharistic life.