Justin Taylor recently posted a fairly lengthy account of the calling and ministry of John Piper. You can read it here. I find his biography to be one of the most fascinating and encouraging of any living ministry on account of the centrality of Scripture, the glory of God and Jesus Christ in his testimony. I concur with Richard Muller, that Piper’s book on Romans 9:1-23 is one of the most scholarly treatments out there (though I do not personally agree with Piper’s conclusions on an eschatological hope for ethnic Jews). If you have not heard Pastor John’s testimony or read the account of his transition from seminary professor to passionate preacher and pastor, I highly recommend that you read this post.