One of the best books I have read in a long time was John Piper's God is the Gospel. As soon as I was done, I started right over at the beginning, and am reading it again now. It is required reading (especially chapter two) for all those believe that gospel purity can be accomplished by means of setting up a tiny little evangelical kennel, in which the gospel will be required to be a yippy dog thoroughbred. No, the gospel is as wide as the character of God Himself, and is therefore something which encompasses heaven and earth, and all that they contain. This is not to say that everything is the gospel, but it is to say that the gospel pervades everything. This includes, as it turns out, the sex lives of upscale urban professionals . . . who will almost certainly find a plain statement of this cosmic reality as judgmental and offputting.