One of the urgent needs of the church these days is to understand the ecclesial significance of controversy. To put it more plainly, we need to remember that conflict in the church is not necessarily a matter of revolt against and defence of a settled solution, but a God-given means of discovering what it is we actually believe. This is how the formulations of the classical creeds occurred: as questions arose, often far more bitterly and violently than in our own day, theological argument gradually found out its own rhythms and norms, and the figure hidden in the mass of as yet undifferentiated or half-articulated belief began to be made visible. So where controversy arises over matters not very fully dealt with so far in the history of our traditions, we should expect to learn something about both our methods and the substance of belief as the debate unfolds – whatever middle-term resolutions it comes to, and whatever long-term expression of ‘orthodoxy’ is agreed upon.