It should now be clear that there are two quite different models of ministry at work in the evangelical Church today, and theology is located quite differently in each. In the model of the Church that has its roots in the Reformation and in the Puritanism that followed, theology is essential and central; in its modern-day evangelical descendants, however, theology is often only instrumental and peripheral. In the one, theology provides the culture in which ministry is understood and practiced; in the other, this culture is provided by professionalization.
The difference between the two models is not that theology is present in one but not the other. Theology is professed and believed in both. But in the one, theology is the reason for ministry, the basis for ministry; it provides the criteria by which success in ministry is measured. In the other, theology does none of these things; here the ministry provides its own rationale, its own criteria, its own techniques. The second model does not reject theology; it simply displaces it so that it no longer gives the profession of ministry its heart and fire.
 David F. Wells, No Place For Truth Or Whatever Happened to Evangelical Theology? (Grand Rapids, MI: Wm. B. Eerdmans Publishing Co, 1993), 254-255.