The controversy: The Basis of Doctrine
One of the largest controversies in the Western church -- at the heart of the divide between Protestants and Roman Catholics -- is the question of how the church forms its beliefs and teachings. On the Roman Catholic side, the view is that the Church wrote Scripture as an instrument for teaching. On the Protestant side, the view is that the Scripture records what the apostles taught. In the earliest decades of the church there is very little difference between those views because the earliest decades were marked by the apostles and those who learned directly from them. But as the voice of the apostles faded from living memory and was preserved in writing, the two roads diverged.
(From the outset I'd like to be clear: I would be glad for suggestions from Roman Catholic readers if there is any way in which I can be more accurate about their teaching.) On the Roman Catholic view that the Church wrote Scripture as an instrument for teaching, it follows that the Church has the key position in deciding what is taught and how it is interpreted. The Roman Catholic church claims the continuing authority to develop teachings, and to teach them with the same authority as Scripture: the authority of the church.
There are other kinds of questions too, that involve either questions of church practice or questions of actual historical events: Since Peter was married and is considered the first Pope, why can't other popes be married? Or if nobody ever asked Mary whether she remained a virgin until the end of her life, on what basis is there a teaching involving that?
Another, less obvious issue again has to do with questions of changing doctrine. Take, for example, the previous discussion of controversies over creation and evolution: many Protestants have decided that it is a mistake to believe in a literal six-day creation. Is that "literal six-day creation" to be considered a mistake in the Bible, or a mistake in the early church's interpretation? On the view that it is a mistake of some kind, how does someone hold that view without savaging those who hold to the ancient interpretation (or, as those groups would say, hold to the plain meaning of the text)? Is there any way to come to an authoritative agreement over interpretations of the Bible, if the authority resides in the Bible or the apostles or God but not in the church? Is there any way to preserve unity with those who disagree?
In the early years of the Christian church, the two views were not so different: whether the Bible teaches what the church teaches, or whether the church teaches what the Bible teaches. At this point, while Roman Catholics and Protestants have gone down their different roads, we are both meeting the same kinds of problems. Some problems have to do with changing teachings: the question of whether we should change, and on what authority. Other problems have to do with claiming that there is an unchanging basis, in the face of these kinds of changes. And the question of making a change is a question that both groups face: if we don't have some unchanging basis, then what defines us?
As Christians, we are ultimately Christ's people. But can we agree on what that means for what we teach?