One of the more helpful works I have read concerning gospel-centered Christianity is Jared Wilson‘s Gospel Wakefulness. Perhaps most insightful to me was Jared’s point that gospel-centeredness can be explained but cannot be taught. In other words, it requires a grace of the holy spirit. I do not think this realization moves gospel-centeredness into a neo-gnostic or higher life kind of category. It simply is the realization that it is God who must work in us in our sanctification. Thus the phrase Jared Wilson uses is Gospel Wakefulness.
In this video, Jared Wilson explain what Gospel-Wakefulness is. This is not a short video, by any measure. But it is worth taking the time – whether in one sitting, or in a series of starts-and-stops.
GRACE & PEACE 
When a person explains any kind of concept, they are in effect teaching. So, the statement that something can be explained but not taught seems to me be self-defeating. 🙂
Jim, Good point. I was paraphrasing off the top of my head the gist of what I recalled Jared Wilson had written. So I pulled the book off my shelf, and here is the paradox he actually asserted: “I can teach about gospel wakefulness, but gospel wakefulness cannot be learned.” He then goes on to explain that it requires a work of the Holy Spirit, and that there are two requisite conditions in which, or two steps through which, gospel wakefulness flourishes: “Utterly Broken” and “Utterly Awed (by God and his love and grace to us in Christ)”.
That makes more sense!