Our paradigms of reality determine how we process informational data. It determines what we make of it (to speak in everyday terms), for processing data is essentially a matter of fitting the bits into our overall frame of reference. In this way paradigms become the pathway to understanding - if the paradigm is a good one, or to misunderstanding if it is not. The point Packer wants to develop is that in a post-Christian culture like ours the preacher of the gospel needs to be aware that the paradigms that currently possess people's minds rarely match the Christian paradigm that controls his own thinking. Packer argues that preachers for our time need to understand the paradigm shifts that have taken place in our culture with regard to God, man and religion, and to equip themselves for the task of reversing them.