What Walther wrote about the Missouri Synod of his time applies just as much to the ELS today. Please note that Lutherans (in the Lutheran Confessions to which Walther refers) distinguish between scriptural doctrine and practice, which is beyond compromise 1, and certain opinions or customs that are neither commanded nor forbidden 2 by Scripture. It would be most uncharitable toward Walther to assume that he is here refusing to compromise in the latter category in any circumstance.
Contrary to our detractors, the Missouri Synod has never claimed to be the only church outside of which there is no salvation. No, not at all.
We do believe that the teachings of the confessions of the Evangelical Lutheran Church, the Book of Concord of 1580, are in fact the pure, divine truth, because they agree with the written Word of God on all points. It is for this reason that the Lutheran church, and consequently our Synod, demands of all members, especially of our ministers, that they acknowledge the Lutheran Confessions without reservation and show their willingness to be obligated to them. And it is precisely because we so value and honor the purity of the Gospel given as a gift to us that we stand with Scripture (1 Cor. 1:10; Rom. 16:17) and our Confessions (AC VII; FC SD X) in rejecting every fraternal and ecclesiastical fellowship that rejects the truth of the Lutheran Confessions, either in whole or in part.
Therefore, our Synod wants to be a church body that knows what it believes and remains ever committed to the same. Will there be lumps that we have to take for this? Most certainly! The people of God have never had any other experience. But will God bless? Most assuredly! For this is the sure and certain promise we have from Him in His Almighty Spirit-filled Word.
Therefore, as president of our Synod, I do not hesitate for a moment to offer you this strong word of encouragement: Continue to sound the clarion call for true, orthodox, confessional Lutheranism. We want no poor imitations, but the real thing in our Synod. Continue to call for complete faithfulness to God's Word and the Lutheran Confessions, recognizing the blessing that such faithfulness has been for our Synod down through the years. And the same holds true also for continuing faithfulness to Lutheran Confessions. Our desire is always to be maximally faithful, not merely minimally so.
With this call for faithfulness comes the Lord's call for outreach. In no way must we ever permit ourselves to pit faithfulness against outreach. Faithfulness to the Word results in outreach with the Gospel. Faithful outreach is based entirely on a faithful proclamation of the Word. The constant hallmark of a genuinely Lutheran Synod, and a genuinely Lutheran congregation, is this two-fold emphasis: faithfulness to Scripture and the Confessions, and outreach with the Gospel.
God forbid that we would ever apologize for wanting to be and remain a truly Lutheran church, or that we would ever hesitate clearly to speak up when we notice others walking away from the truths of the Word and the Lutheran Confessions for the sake of unity, which is no unity at all, since it is not based on agreement in the teachings of the Word, but only on an agreement to disagree!
Thus, we pray that the Lord would continue to strengthen and embolden us to be a true, faithful and courageous Lutheran church body, to the glory of His holy name and the extension of His kingdom.
From C.F.W. Walther, The True Visible Church, translated by J.T. Mueller (St. Louis: Concordia Publishing House, 1961).
[1] Common examples: that the Bible is (not contains) the inspired, inerrant Word of God.
[2] Common examples: whether to sing hymn 250 or 251 or 252 in a particular service, some of the qualifications for ushers, the decor of the Church sanctuary, where a congregation conducts its worship services, whether to use glass or plastic "dixie cups" to hold the blood of Christ. Note that this is where 1 Corinthians 10:23 applies.