A worthy quote from Franz Pieper, 20th century Lutheran professor, pastor, and dogmatician. Pieper manages to hit both sides of the equation: we love unity, value it, and work and sacrifice to preserve it, but not at the expense of our doctrine, which isn’t ours at all, but rather the God of heaven’s. It belongs to Him because He gave it to us in His Word. Both halves are necessary. One without the other is unBiblical imbalance. Unity without agreement in doctrine is unionism, false eecumenism, declaring agreement where none exists, and doctrine without unity can become sectarianism, Pharisaism, and loveless legalism. Genuine, authentic, vibrant Lutheranism (and Christianity, for that matter) calls for both unity and doctrine together.

Pieper’s also right on when he observes that personal differences or disagreements often fester and erupt into doctrinal controversies and schism. Church politics are just politicking that happens to take place in the church. For this reason I despise church politics and avoid it like the plague. Doctrine gets steamrolled or sidelined when the career politicians start in, whatever the venue. When the doctrine is forgotten, the powerful trample on the weak and defenseless… if we’ve seen it once we’ve seen it a hundred thousand times in the history of the Church. For that reason we need brave people who are not unafraid to stand on God’s Word when the occasion calls for it.

Thesis XIV reads: “The Evangelical Lutheran Church observes
the unity of confession and love toward all who share with it the one faith.”

This corresponds to Ephesians 4:3: “Be diligent to keep the unity of the Spirit which is effected through the bond of peace.” The unity of spirit is the unity of faith which is effected by the Holy Ghost. Wherever this is present,
the proper unity desired by God is also present. We are, moreover, to cultivate this unity. It is imperative for us to avoid with all caution anything which might threaten it. It is also important to keep in mind that personal motives
often are at the bottom of disunity. Pastors and other official teachers in the church become hostile toward one another, and this enmity of the heart soon gives rise to separation in doctrine and belief. The Bible says: “Be diligent to keep unity of the Spirit through the bond of peace.” One is not merely to receive the unity of spirit as something which is brought about of itself, but it requires the application of all diligence to preserve it.

The Formula of Concord states (p.553,7): We believe, teach, and confess also that one church should not condemn
another for having fewer or more numerous outward ceremonies which are not commanded by God, if otherwise they are in agreement on ALL the same articles and properly employ the sacraments, in keeping with the well-known dictum: Dissonantia jejunii non dissolvit consantiam fidei (differences about fasting
should not divide the unity of faith)
[Trig., p.830].

Our confession states here what the prerequisite is for external union, namely, the agreement in doctrine on all of the same articles. “All” has been capitalized in this present quotation in order to point out that our confession has a very different understanding of church unity than the unionists of our day. The unionists today assert: If there is agreement in several of the chief articles, then many other differences can be overlooked. Our confession, however, states that while we do not require conformity of practice, because it is not commanded by God, we do nevertheless insist on doctrinal unity in all the same articles commanded by God. If we wish to acknowledge a church body as orthodox, it must be in agreement with us on all articles of doctrine.

from Franz Pieper, “The Church and Her Treasure, Twenty-third Lecture” (p.276-277)