5. Church fellowship with heterodox churches is against the divine order. (Unionism)
As is well known, the fact that there are children of God in irreligious churches is cited as a reason why it is right, indeed required by love, to make fellowship with heterodox churches. Scripture teaches just the opposite,
1553) St. L. IX, 44.<w:t xml:space="preserve">1554) The evidence in Baier III, 646 ff.
1555) Walther, Kirche u. Amt, pp. 95-113. [Walther and the Church, p. 65]
1556) K. u. A., p. 160 f. [Walther and the Church, p. 70]
490 > The Christian Church. [English ed. ~ 425-426]
namely, "Depart from the same!"1557) The unionist argument is also naturally unreasonable. The old Lutheran doctrines point to 2 Sam. 15:11 as an illustration. As little as the fact that two hundred citizens of Jerusalem went with Absalom out of ignorance entitled the rest of Israel to join the rebel camp or even to flirt with the rebels, so little does the fact that a number of Christians make fellowship with false teachers out of ignorance against God's order entitle other Christians to do the same. To invoke love for this purpose is an abuse of the word. Love for God and for the brethren demands just the opposite. He who loves Christ also loves Christ's word, and to Christ's words belongs above all the word of shunning all those who teach something other than Christ's word. And to love the brethren belongs first of all also the practice that we do not err and sin with them, but seek to rid them of error and sin. Finally, the Scriptures of the Old and New Testaments expressly declare that God sends false teachers so that Christians may avoid them, not so that Christians may have fellowship with them.1558) Disobedience to the divine commandment forbidding Christians to fellowship with false teachers and false doctrines is called in church parlance "unionism," "religious mongering," "syncretism," and so on.1559) Unionism is actually the cause of the existence of divisions and heterodox churches in Christendom in the first place. If all Christians had kept to the divine order of shunning those who teach differently (ετεροδιδασκαλονντες), neither the Papacy nor other sects would have arisen. Where there are no buyers, there is no market. Unionism, to be sure, pretends to want to eliminate disunity within Christendom. But because the unity of the Christian church is a unity of faith and confession, it is a caricature of Christian unity, indeed a mockery of it.1560) Instead of healing the damage, he declares it in permanence. An exact description of the Christian unity we have 1 Cor. 1:10: "I exhort you
1557) Rom. 16:17; 1 Tim. 6:3 ff.; 2 Joh. 10. 11 etc.
1558) Deut. 13:3; 8:2; 1 Cor. 11:19.
1559) Baier III, 665 sqq; Apol. 162, 48.
1560) Cf. Luther on the unity of the Christian church as a unity of hearts through faith in the Word of God, St. L. XIX, 344 ff.
491 > The Christian Church. [English ed. ~ 426-427]
but, brethren, by the name of our Lord Jesus Christ, that ye all speak one thing (ΐνα τό αυτό λέγητε πάντες), and let there be no divisions among you." Here agreement in address (λέγειν) or confession of Christian doctrine is required. And when the apostle continues, "But hold fast one to another in one mind and in one opinion (εν τφ αντφ νοι και εν avxfj γνώμγῃ)," it is clearly expressed that Christians are to understand the same words in the same sense.1561) Agreement in the same words in different senses is the very opposite of the unanimity wrought by God, and if such unanimity is sought, it is gambling indecent to Christians in holy, divine things.1562) The Christian church can and should be patient with the erring and seek to remove error through instruction. But it can and should never grant error a right alongside truth. If it does so, it is always a denial of the truth itself. Truth has it in itself that it excludes the opposing error. Truth, which no longer excludes error from itself, but grants it the right to exist beside itself, gives itself up eo ipso as truth. Luther's words belong here, such as these:1563) "He who holds his doctrine, faith, and confession to be true, right, and certain cannot stand in the same stall with others who lead false doctrines or are devoted to them." This is why the unionism of the Christian church is so dangerous, because it abolishes in principle the difference between truth and error, and it can happen only as a result of a "happy inconsistency" that he who makes fellowship with error nevertheless remains for his person essentially on the ground of truth. For it is indeed a "happy inconsistency" if someone, although he accepts those words of Scripture which teach the difference between the truth and the error of those who teach it
1561) Meyer on this passage: is nowhere in the New Testament called Gesinnung, but sententia, iudicium."
1562) Cf. Luther XVIII, 1996: "Fabius teaches that an ambiguous word should be avoided like a cliff, and if such a thing should happen to us, it can be forgiven; but to seek it with diligence and resolution is not worthy of forgiveness, but of the most justified hatred of all. … For if one were to get into the habit of speaking doubtfully and cunningly in religion, in law, and in all important matters, what would become of it but a completely confused Babel, so that in the end no one could understand the other?"
1563) St. L. XVII, 1180.
492 > The Christian Church. [English ed. ~ 427]
but still holds fast to the words: "The blood of Jesus Christ, the Son of God, makes us clean from all sin. 1564) — As for the address that is found in our time even among so-called positive theologians, that "different trends", that is, disagreement in doctrine and confession, are intended by God, one can only wonder that such address is heard in the face of the contrary testimony of Scripture within Christendom.