It is obvious that all who err with regard to the distinctive doctrines of the Christian religion must err also with respect to the doctrine of the Church. Of all errors concerning the Church the foremost is that the Church is an "outward polity" (externa politia, "aeusserliche Polizei" "Heilsanstalt") "of the good and wicked" Apology, VII (VIII), 13 ff., to which persons are joined by their external membership.
Closely related to this error, which pertains to the essence (forma) of the Church, is that regarding its purpose, namely, that the Church is a "society for the sanctification of its members" or that it is an organization whose object is to save souls by means of good works. These basic errors are not incidental, but rather the result of the rejection of the fundamental Christian article of justification by grace, through faith.
In fact, all who repudiate the satisfactio vicaria, the efficacy of the means of grace, and the sola fide must of necessity regard the Church as a sort of reform school in which men are to learn how to be good and so to merit salvation. On the other hand; the Biblical doctrine of the Church is built up on the central doctrine of justification by grace, through faith, so that it stands or falls with that doctrine. In particular it rests -
a.Upon Chris's vicarious satisfaction. According to Scripture the Church consists of all those who believe in the Christ who died for the sins of the world. All who refuse to believe this are outside the Church, 1 Pet. 2, 8. This doctrine is opposed by all rationalists (Photinians, Socinians, Unitarians, Modernists, etc.), who reject the doctrine of salvation by faith in Christ's blood, 1 John 1, 7, as an "obnoxious blood-theology" and to whom the Gospel of the crucified Christ is both foolishness and a stumblingblock, 1 Cor. 1, 23. Hence they have no other way of defining the Church -if they at all care for a church -than as "a free society of rational beings for the realization of earthly and heavenly happiness, conditioned by man's religious illumination and virtue" (Roehrs).
More simply defined, the Church, according to all rationalistic theologians, is a society of men who wish to secure happiness in this world and the next by means of religious devotions and other good works. In their estimation the Church is only a "moral or ethical society" and embraces as members all who are willing to perform the duties which it imposes.
As all rationalists in general, so also the rationalistic papists in particular regard the Church as a pious society of men sanctifying themselves by good works. According to the papistic doctrine a person does not become a member of the Church through faith in Christ, but through his professed willingness to obey the instructions of God and the Church (Council of Trent, Sess. VI, Can. 20), or through the performance of good works prescribed by the Church (Sess. VI, Can. 32). This basic error really places the papists extra ecclesiam; for Scripture testifies that all who are of the works of the Law are fallen from grace, Gal. 5, 4, and are under the curse, Gal. 3, 10.
The antichristian attitude of the Church of Rome is moreover proved by the fact that it has pronounced its anathema upon the true Christian Church, namely, upon all who believe that they are justified alone by grace, through faith in Christ (Council of Trent, Sess. VI, Cans. 11. 12), defining at the same time the "true Church" (sc. the Roman Catholic Church) as "the congregation of men under the rule of duly called pastors and especially of the one vicar of Christ upon earth, the Roman Pontiff" (coetus hominum . . . sub regimine legitimorum pastorum ac praecipue unius Christi in terris vicarii, Romani pontificis, Bellarmine). Officially Rome thus makes it impossible for its followers to be members of Christ's holy Church.
If Catholics despite the pernicious rationalism of their Church are members of Christ's Church, it is because in their terrores conscientiae they renounce its doctrine of work-righteousness and, contrary to its will and command, believe the sola fide. We therefore recognize the papistic Church as Christian, not inasmuch as it rejects the Christian doctrine in its official theology (decisions and canons of the Council of Trent), but inasmuch as, quite inconsistently with its general theological system, it professes the Apostles' Creed, which acts as a corrective in the case of individual Catholics. Officially Roman Catholicism is not Christian, but pagan, because it professes as its cardinal dogma salvation by works.
Since also many modern "positive" theologians (Hofmann, Kirn) repudiate the satisfactio vicaria, they, too, err in their definition of the Christian Church. According to Kirn the Church is "the communion of the religious and moral life determined by the spirit of Christ" (Ev. Dogmatik, p. 118); that is to say, the communion of all who lead a moral life in the spirit of Christ. This, in the last analysis, reduces the Church to an "ethical society."
Because the Calvinists deny the gratia universalis and the efficacy of the means of grace as the media iustificationis, they also cannot define the Church rightly as the communion of all true believers in Christ, but must regard it theoretically as the "communion of the elect" and practically as the communion of all who possess the gratia infusa, or the immediate operation and indwelling of the Holy Ghost in their hearts. All true members of the Church in Calvinistic denominations repudiate the gratia particularis and in their spiritual distress hold to God's gracious promise which He offers to all sinners in the Gospel. It is on account of this fact that they are members of Christ's Church.
b.Upon the doctrine of the means of grace. By this we mean that without the means of grace there can be no Church. According to the clear teaching of Scripture a person becomes a true member of Christ's Church only by appropriating to himself the merits of Christ, Rom. 4, 3; Acts 10, 43-48. But unless the merits of Christ are offered to the sinner by God through His conferring means (the Word and the Sacraments), man cannot appropriate them at all. The Reformed error of "immediate grace" (Efficaciow grace acts immediately) must be rejected as unscriptural, Rom. 10, 13-17; Acts 2, 38. The Calvinists repudiate the means of grace and thus render faith and justification and consequently the existence of the Church impossible.
For the means of grace some modern "positive" theologians substitute the "Christian experience" (Erlebnistheologie); but the Bible does not recognize the Christian experience as a means of grace. It is rather a fruit of faith. Hence there is only one way in which a person may become a member of Christ's Church, namely, by faith in the divine promises of grace offered in the Gospel and in the Sacraments, 2 Cor. 5, 19-21.
c.Upon faith as the receiving means (medium ληπτικόν). This is evident from the fact that only those are members of the Church who believe in Christ, Mark 16, 15. 16; Acts 16, 31. All who deny faith as the medium .hpm"6v of God's proffered grace are unable to define the Church in its Biblical sense, as the communion of true believers. Those who regard the Sacraments as working ez opere operata (Romanists, Romanizing Protestants) are obliged to define the Church as a communion of men who, by the aid of the Holy Spirit, endeavor to lead a moral life; for with the rejection of the sola fide only good works remain as the means of justification (medium iustificationis).
d.Upon the sola fide. This follows from what has been said before. The Church is the communion of true believers; but true believers are those only who hope to be saved by grace, through faith, without works, Rom. 3, 28; 4, 3-5. For this reason all Pelagians, Arminians, and synergists are compelled either to renounce their doctrine of work-righteousness or to abandon the Scriptural definition of the Church. The history of the Christian dogma proves that quite consistently they abandon the latter and thus regard the Church as the congregation of all who seek salvation by works. Cp. Christl. Dogmatik, III, 464 ff. That they take this unfortunate step is quite logical; for only those can rightly define the Church as the communion of believers who adhere to the Scriptural doctrine of justification by faith (sola gratia).