And there is more to confess here. Consider a statement in that form "X is not necessary for Y." Why are such statements made? For example, these two statements in that form are both true:
A) Saying "I love you" each day to your spouse is not necessary to Christian marriage.
B) Eating a green apple each day is not necessary to Christian marriage.
Both are true, and yet B is almost certainly a useless statement than never needs to be made precisely because eating a green apple has next to nothing to do with marriage, while the communication of love certainly has a lot to do with it. In fact, daily communication of love is so supportive of Christian marriage that someone might be tempted to think that it is the essence of Christian marriage. Hence the need for statement A.
So the need for this confession in AC VII - unity in ceremonies is not necessary for the true unity of the catholic Church, but it is so supportive of that unity that Christians might be tempted to mistake the support for the essence.
Thus, the first generations of Lutheran both confessed AC VII and also insisted on a great degree of uniformity in rite and ceremony, as evidenced by the old Church Orders. Why? Because while not of the esse of the Church, a unity in rite and ceremony is of the bene esse of the Church and very supportive of the esse. That is, worshiping in like manner supports believing in like manner, avoids scandal and division based on church shopping, etc., etc.
There was much good discussion below concerning what level of unity in our outward ceremony would best support both harmony in the Church and Christian freedom.
This discussion will continue at Octoberfest in Kewanee (Have you registered yet? Did you know this is the best party in the Missouri Synod? Will Fr. Fritz ask what the hymn Hotel California means again this year?). In thinking through my response to the questions that the Rev. Editor posed, I'm leaning toward a twofold response. I think there is a basic unity in form of worship that we should insist upon - while yet leaving room for local custom.
In speaking with some members of The Gottesdienst Crowd, I think there is a basic level of unity such that that if we had it, nobody in TGC would complain much at all. Gottesdiesnt would still publish and still advocate the rites and ceremonies we believe best confess our doctrine to the gathered believers and the world at large - but we really wouldn't have much to complain about if everyone in our fellowship:
* Used only rites (the words and order) from one of our books: TLH, LW, LSB, HS98 (or corresponding books, like CW, for other fellowships).
* Used only these books for congregational hymns.
* Utilized music in the tradition of the Lutheran Reformation and the Western Church catholic (= no American Evangelical, soft-rock, culture-capitulating praise bands)
* Vested in a minimum of alb and stole, or cassock-surplice-stole
* Practiced a ceremony that avoids "
* Read from one of the Lectionaries in one of our hymnals.
That list provides a good deal of unity - enough to where visitors from sister parishes would not feel like they walked into another denomination when they come into the sanctuary - while leaving ample room for local custom. And, yes, leaving room for improvement in confessing our doctrine. For example, under conditions of such unity Gottesdienst would still advocate:
* Weekly Communion
* Chalice Only
* Chanting of the Services
* The Common Service
* A Reverent Ceremony consciously informed by historic Lutheran practice and evangelical-catholic piety (genuflecting, traditional use of altar boys, crucifers, Deacons, etc. I have been told those outside TGC call this "chancel prancing.")
* Full Traditional Vestments
* TheHistoric Epistles and Gospels + LSB's 1-Yr. OT selections