From an interview where I asked Kevin Vanhoozer about the important of a sanctified imagination and how to develop it:

First, I find that the imagination is a vital ingredient in my sanctification. I need to keep the big biblical picture (creation-fall-redemption-consummation) in mind as I attempt to live day by day, minute by minute, as a follower of Jesus Christ who desires above all to have one’s thought and life correspond to the gospel. To do that, I have to keep the gospel story (together with its presuppositions and implications) in mind, and I have to connect my story to that of Jesus. That requires imagination.

Second, the imagination is “sanctified” because it is “set apart” for the purpose of making just these kinds of connections.

There are vain imaginings, of course. These tend to be the ones that encourage us to see our lives as part of some other picture where God is either absent or other than the Father of Jesus Christ.

As for practical helps for cultivating a sanctified imagination, let me mention two.

First, reading. Reading is the way we learn to inhabit the world. Not the natural world, but the cultural world: the world of meaning. Martha Nussbaum has some wonderful essays in her book Love’s Knowledge on how the novels of Henry James train us to attend to the moral significance of the details of human life.

If we can learn moral sensitivity from Henry James, how much more can Christians learn, say, about speech ethics from the epistle of James, not to mention all the Old Testament narratives, Jesus’ parables, and the Gospels themselves.

My concern is that many Evangelicals are suffering from malnourished imaginations. This impedes their ability to live coherently in the world—that is, according to a meaningful metanarrative. We want to believe the Bible, but we are unable to see our world in biblical terms. . . . That leads to a fatal disconnect between our belief-system and our behavior, our faith and our life. If faith’s influence is waning, as two-thirds of Americans now think, I believe that it is largely because of a failure of the evangelical imagination.

Reading, then, is a kind of strength-training that flexes the muscles of our imagination. Those who read widely are often those who are able to employ metaphors that connect ordinary life to the wonderful real world of the Bible.

The second way I exercise my biblically rooted, theologically formed imagination is by viewing myself as part of the ongoing action that the Bible recounts. My task as a disciple of Jesus Christ is to continue the theodramatic action—the plot of salvation history—in a manner that is consistent with what the Father, Son, and Spirit have already done and are still doing. To some extent, the theologian is a worker in dramatic fittingness whose task is to help us understand the drama of redemption, both theoretically and practically. We need practical understanding of the gospel so that we can speak and act faithful and orthodox lines in new cultural scenes. It is by seeking to live by the word in the power of the Spirit that our imaginations become sanctified. I need a sanctified imagination as I seek each day to improvise my life to the glory of God.