Patristic AttemptIn the earliest post-apostolic days, the church fathers spoke of the "canon of truth" or the "rule of faith." The legitimacy of both Christian and church depended upon unswerving allegiance to the core doctrines of Christianity.
Constantinian AttemptDuring the age of the ecumenical councils, Christians began to build consensus around four "marks" of authentic churches as articulated in the early ecumenical creeds. The Council of Constantinople (AD 381) first published these four marks, speaking of the One, Holy, Catholic, and Apostolic church. Thus, any congregation not in unity with other congregations, not holy, not worldwide in scope, or not connected to the apostles was not a valid church. The interpretation of these four marks varied (as it still does), and this variance at times provoked intense controversy among Christians. Yet most Christians agreed that these four words, in at least some vein of interpretation, distinguished valid churches from invalid churches.
Since mainstream Roman Catholic interpretation of the four marks came to dissociate holiness from any visible attribute of the actual earthly people or institutions associated with the church, and since Roman Catholic interpretation tied apostolicity with a delegated authority to contemporary officials and an ever-evolving body of church tradition, in the medieval period in the West the four marks as applied basically came to signify the approval of Rome. If the Pope affirms you to be such, you are a part of the one, holy, catholic, and apostolic church.
Reformation AttemptThe Augsburg Confession stated:
It is also taught that at all times there must be and remain one holy, Christian church. It is the assembly of all believers among whom the gospel is purely preached and the holy sacraments are administered according to the gospel.The Reformation tied the validity of the church to the gospel it proclaims and the way it administers baptism and the Lord's Supper. One almost sees here the basis for the later theology of J. R. Graves, although Luther interpreted these "sacraments" differently than Baptists do. Nevertheless, the Reformers certainly argued that the absence of rightful proclamation of the Word or the absence of true gospel "sacraments" necessarily marks the absence of a valid church.
Next time, a consideration of several Baptist statements about invalid churches. Yes, for those of you whose mouths are watering, this will include Landmarkism.