What is the nature of the bond among members of a liturgical assembly that makes it different from a 4H-Club (pure voluntary organization) or a family (pure non-voluntary organization)? As but part of the visible Church, the liturgical assembly cannot, except derivatively, be taken as the Church itself. In other words, the liturgical assembly is a sign of the family, not the family itself, nor even a family within The Family, just as the bread it breaks sacramentally signifies and presents the Body in Christ but is not itself the Body. At the same time, as no one partakes of the Holy Communion without actually eating and drinking the elements, so also is there no salvation outside the Church, and no mystical reality without visible reality.
Living requires regular communion, both in reception of the sacrament itself and in the social fellowship that it implies. Without eating and drinking with faith and being caught up in the one sacrifice of Christ, in vain do we ‘offer and present [to the Lord] ourselves, our souls and bodies, to be a reasonable, holy, and lively sacrifice’; without living under the particular assembly’s oversight, in vain do we claim the Church. So particular membership is necessary as particular reception of the Eucharist is necessary. The particular assembly, where God engages his people in the liturgy of word and sacrament, is the normal place in which faith is born, nurtured and sustained.
In a Church visibly united, one assembly’s oversight is the oversight of all, or on behalf of all, and so transfer from one assembly to another does not compromise churchly discipline. With doctrinal and (informal) disciplinary unity, even church-hopping is mostly a matter of personal stability, not of breaking bonds or abolition of accountability. When the Church is one not only in doctrine but also in action, Christians are not given to the kind of shopping that insulates them from those whom they would cut off from themselves. Even if in practice they gather mostly with those who are similar to themselves, their choice of liturgical assembly is not itself a Church-splitting move. Indeed, they may have joint assemblies from time to time, cultivating longsuffering and love toward those whom they do not naturally always ‘fit’ with.
In a fragmented Church, however, where letters of dismissal are no longer the norm for transferring membership from one liturgical assembly to another, the reality is more complicated. Alarmingly common is the ‘soft schism’ of agreeing to disagree, allowing believers mutually to depart like heathen spouses, without attempting any but subjective unity. In this context, church transfer taken in hand unadvisedly or lightly is much to be opposed, as a way of satisfying men’s carnal lusts and appetites, particularly the appetite for schism and autonomy. Such action, indeed, is sacrilege, dissension and sedition against the rule of God. In maintenance of catholic doctrine and catholic comprehensiveness against both heterodoxy and sectarianism, parishioners ought to be exhorted to stay even when serious theological differences have become apparent.
 Thus do we sometimes call the liturgical assembly a church, as the Second Helvetic Confession, xix, testifies of the sacraments: ‘And as we learn out of the Word of God that these signs were instituted for another purpose than the usual use, therefore we teach that they now, in their holy use, take upon them the names of things signified, and are no longer called mere water, bread or wine, but also regeneration or the washing of water, and the body and blood of the Lord or symbols and sacraments of the Lord’s body and blood. Not that the symbols are changed into the things signified, or cease to be what they are in their own nature. For otherwise they world not be sacraments. If they were only the thing signified, they would not be signs.’ ↑
 For another eucharistic take on the liturgical assembly (or ‘church’), but one that does not presuppose finitum non capax infiniti, see Alexander Schmemann, ‘The Idea of Primacy in Orthodox Ecclesiology’, in The Primacy of Peter: essays in ecclesiology and the early church, ed. John Meyendorff (St Vladimir’s Seminary Press, 1992). A Protestant theopolitical theory, of course, requires significant adjustments to Schmemann’s articulation. Perhaps the necessary adjustments can draw from James Ussher’s synodical reduction of episcopacy (1641), also reviewed by Dirk C. Reinken. ↑