T.A. Noble (Holy Trinity, Holy People, 7) says this about the role of the Bible in theology in a discussion of the Wesleyan Quadrilateral (which, he rightly says, isn’t just Wesleyan):
It is not the task of theology merely to expound and elaborate and refine the church’s doctrine: that would be a traditional Roman Catholic view of its function. Rather, [the primacy of Scripture] gives dogmatic theology a critical function, namely, in every generation to judge the doctrinal statements of the church against the criterion of Holy Scripture. Biblical exegesis, that is to say, must not be held captive to dogmatics, as it was in the pre-Reformation Catholic church or (in effect) in the age of Protestant scholasticism. As far as within us lies, exegesis must not become eisegesis, reading into the text our own doctrinal formulations. Rather, with the reverent, godly use of the tools of biblical criticism, purged from unbelieving and secular presuppositions, the text must be allowed to speak its own message and we must strive to allow it to call in question our understanding of the truth, our doctrinal formulations, so that they may be deepened and expanded and, if need be, corrected. In this way an ongoing dialogue takes place in which the living church of God with its doctrinal formulations listens again and afresh in every generation to the Word of God, and, in the light of new questions and new insights, deepens and corrects its understanding of the truth.
I suspect this is unfair to “traditional Roman Catholic” theology, and it’s unfair to Protestant scholasticism, but he’s got the purpose of theology right. It is, as Barth put it, a matter of testing the proclamation of the church by the standard of the Word of God. And, Barth again, any theologian who is doing his job will not be able to come back with a “all clear, no problems” report.