More from the Volf article (wow, he sounds like Soren K. here):

I asked whether a fruitful theological discussion is difficult with those who aren't committed to the authority of Scripture. "I don't feel that at all," he replied. "I think there are people who affirm the most strict understanding of scriptural authority but find zillions of ways of transgressing theologically and personally against it. The question of authority is important, but the central question is how the Bible functions in theology and life. I think evangelicals would do better if they concentrated less on bolstering the formal authority of the Scripture�which I certainly would want to affirm�and more on displaying how biblical texts can shape lives in salutary ways, how they are fruitful texts, how they are texts one can live according to. I think that would do more to establish the authority of Scripture than the formal assertion of the authority of Scripture."