John Piper discipled me in my car when I attended Dallas Theological Seminary. I used to listen to his sermons as I would commute to and from work and school. Throughout my career in seminary, the Lord used John Piper to shape my thinking about God and the scriptures more than any single teacher that I ever had. I know of no preacher who combines exegetical, theological, and devotional depth like Dr. Piper. His ministry, which is called “Desiring God,” makes all of his sermons (manuscripts and audio) available for free at http://www.desiringgod.org/. I am teaching on Romans 12:1-2 in a Sunday morning bible study at my church. As is…