Prophetic speech and action have been regarded with suspicion both in the old Israel and in the new. The doctors and lawyers of the church have sought to apply the brake (“Prophesy not any more in Bethel…”). In the past, theological dealing with prophetic movements has often been haphazard, unsympathetic, or scholastic. We stand now at some watershed of history. It is of urgent importance that sound theology and right action should have a church wedding. In this article I hope to do no more than draw attention to the danger that theological thinking to-day may do less than justice to prophetic action. The theologian may misinterpret the nature and scope of his task. My concern that this should not happen is sharpened by my membership of a movement which I count prophetic, the Iona Community (though in this article I speak personally, in no sense as the Community's representative). Where any such movement exists the theologian has inevitably his contribution to make. There is the obvious need to sift affirmations and scrutinise methods. It is the manner of that contribution which requires careful thought.