Enns is in good conservative Reformed company in what he's doing in Inspiration and Incarnation, following Herman Ridderbos, for example:
“From the standpoint of faith, the nature of the Scripture and its authority can surely be more sharply, clearly, and precisely distinguished when we see the Bible against the background and in the light of the time in which it was written. Then we come to see on the one hand the incomparable otherness of Scripture, and on the other that which is bound up with and limited to the time.”
“…[R]emember that just those who have occasion to come to a more historical approach to the Bible and its authority will be able along the way to understand the unique and incomparable significance of Scripture. The world of the ancient Near East is being increasingly opened to us. We are discovering very ancient ‘literature’ in which the religious feelings of people who were contemporaries of the biblical writers are expressed. There is increasing Jewish background through the Talmud and through insights into the radical movements in the Judaism of Jesus’ time through the discover of the Qumran writings…All of this teaches us more strongly than ever to be mindful of the relationship between Scripture and the world out of which it arose..there is nothing that more clearly brings to the light the unique character of the Scriptures than the qualitiatve comparison between that which here and that which there steps out to meet us…
…in light of *this* authority authority, we can overcome the fear that we may be on a dangerous pathway if we view the ways of the Spirit in recording the word of God more historically, more critically, as more shaded, than along the way of an exclusively dogmatic reasoning.”
(Ridderbos, Studies in Scripture and Its Authority, 10, 35, 36)
Generally speaking, it seems to me that the Old Princeton concordist attitude toward biblical studies promotes this kind of approach to discerning what type of authority we should say that scripture actually has.