The Reformation was not a movement that created a new church. It was a movement that led one part of the church to reform itself by the Word of God and another to reject the particular work of the Spirit’s renewing ministry in the sixteenth century.
When Luther walked to the University Church in Wittenberg, around noon on October 31, 1517, he did not think to himself, "Today I am going to reform the church. I will make claims for biblical renewal and the result will be a great church split, resulting in a new Protestant Church." He not only had no plans for a new church he still wasn’t even sure whether or not indulgences were right or wrong. He simply knew that profiteering in spiritual things was wrong!
The magisterial Protestant Reformers were most definitely not innovators. And they never desired two churches. They wanted to correct a number of moral and doctrinal abuses by the Word. And they understood that the Word was the gospel of Christ, not just any word from any text. These were not proof-texting radicals. They were faithful sons of the church who longed for new mercies to break upon the visible church and their age with gospel power.
The separation that came about in the sixteenth century needs to be considered much more carefully. Luther never left the church, nor did he ever desire to leave it. The European division resulted in two great streams of Western Christianity, Protestant and Roman Catholic. But the Protestant stream is much better understood as Evangelical. The Reformers used this word, more than any other, to describe what they saw and believed. In their view the church was to be defined by the gospel, not the reverse. So it is to this present day. When the church, Protestant or Catholic, defines itself by itself, or defines the gospel by the church (by its confessions, creeds, traditions, liturgies, etc.) it shuts out the power of the gospel.
This does not mean that creeds, confessions and liturgies are unimportant or irrelevant. Quite the opposite. But it does mean the Word (Christ in the gospel) judges the traditions and confessions of the church! The danger modern Reformed and Lutheran conservatives face is very real at this point. They have a strong tendency to judge everything by their creeds and pratices. Reformation is then seen as restoring our creeds, reacting to "seeker" churches, and in general being oppositional to anything modern and deemed too friendly to popular culture.