I’m not a preacher, but I have occasionally played one when asked to fill in. Of the few times I have done so, there is really only one that I can look back on with any satisfaction that I did right with that responsibility. On that occasion, I chose Romans 12:1–2 for my text.

I beseech you therefore, brethren, by the mercies of God, that ye present your bodies a living sacrifice, holy, acceptable unto God, which is your reasonable service. And be not conformed to this world: but be ye transformed by the renewing of your mind, that ye may prove what is that good, and acceptable, and perfect, will of God.

Since then, I have always been interested in seeing how real expositors handle that text. I am always gratified to find that I didn’t botch it completely, and in fact agreed almost entirely with those who know far better than I. However, I am also severely humbled to see how much I missed. (Would you believe my “exposition” was only twenty-five minutes long? I missed a lot.) Luther heaps more shame upon me:

   Be ye transformed by the renewing of your mind (12:2). In this way the Apostle describes (Christian) progress; for he addresses those who already are Christians. The Christian life does not mean to stand still, but to move from that which is good to that which is better. St. Bernard (of Clairvaux) rightly says: “As soon as you do not desire to become better, then you have ceased to be good.” It does not help a tree to have green leaves and and flowers if it does not bear fruit besides its flowers. For this reason — (for not bearing fruit) — many (nominal Christians) perish in their flowering. Man (the Christian) is always in the condition of nakedness, always in the state of becoming, always in the state of potentiality, always in the condition of activity. He is always a sinner, but also always repentant and so always righteous. We are in part sinners, and in part righteous. No one is so good as that he could not become better; no one is so evil, as that he could not become worse.
   This (fact) the Apostle expresses very nicely by saying “Be ye transformed by the renewing of your mind.” He adds “By the renewing of your mind” to stress that renewal of the mind, which takes place from day to day and progresses farther and farther, according to the words, II Corinthians 4:16: “The inward man is renewed day by day”; of Colossians 3:10: “Be ye renewed in the spirit of your mind” or “Put on the new man, which is renewed in knowledge after the image of him that created him.”

—Martin Luther, Commentary on Romans, trans. J. Theodore Mueller (Grand Rapids, Zondervan, 1954), 151–152.

What a rich passage this is! Maybe I’ll live long enough to thoroughly appreciate it. I have long said that being a Christian is not a matter of doing, but of being. I think I’ll have to replace being with becoming.