The original draft of the Apostles' Creed confesses: "I believe in ... the holy, catholic Church." Over time, it changed into "the holy, Christian Church." Both confess that there is one church, just as there is one kingdom of God, not competing kingdoms of God.
The Evangelical Lutheran Church has always confessed and claimed that it is the church catholic. In other words, we are not a sect which has branched off of Christendom. We have retained the confessions that the Christian Church has always taught. The Augsburg Confession and the Apology of the Augsburg Confession take great pains to say so.
The Lutheran Reformation was not a rebellion or a revolution. It was a conservative Reformation, which means to say that it strove to retain what the Christian Church practiced in regard to rites and ceremonies, as much as Scripture allowed it to. That is why some come to Divine Services in the Lutheran Church and comment, "That looks just like a Catholic service!"
In my corner of Lutheranism (Wisconsin Evangelical Lutheran Synod), and perhaps in others, this comment is often met with a visceral reaction in which people try to distance our church as far as possible from Rome. While Evangelical Lutherans have maintained our protest against Rome (cf the above confessions, as well as the Smalcald Articles for the reasons for such protests and division), there is still much which we practice which continues the tradition of the western church . The fact is, we are a catholic church, though not Roman, and our worship ought to confess that. That means we follow the western rite (the Common Service is our version of that), the Church Year, the use of vestments, et al. There is no need to apologize for it, much less to distance ourselves from it. Our continued use of these ceremonies and rites testifies that we are the church catholic.
With that in mind, consider this Summer Reading Snippet from The Conservative Reformation and Its Theology by Charles Porterfield Krauth:
"We are not so much alarmed therefore, as some men pretend to be with mere coincidence with elements existing in the Romish Church. If anything in our Protestant doctrines or usages be, indeed, a perpetuation of what is unscriptural in the Romish system, it should be weeded out; but it does not follow, that because a thing is in Rome, it is of Rome." (p 342, emphasis original)