In a footnote in The Erosion of Inerrancy in Evangelicalism, G.K. Beale offers a helpful explanation for a how a biblical theological approach to hermeneutics  reads the Bible.   He writes,

A biblical-theological approach attempts to interpret texts in the light of their broader literary context, their broader redemptive-historical epoch of which they are a part, and to interpret earlier texts from earlier epochs, attempting to explain them in the light of progressive revelation to which earlier scriptural authors would not have had access.  So one aspect of biblical theology is the reading of texts in an intratextual and intertextual manner in a way not ultimately distorting their original meaning, though perhaps creatively developing it (105).

Well said.  

Sola Deo Gloria, dss