Presumption Produces Self-Deception

“For if anyone thinks he is something, when he is nothing, he deceives himself.” (Galatians 6:3)
Last week in this post I made the point that regardless of how well I think I’m doing in the sanctification project or how much progress I think I’ve made since I first became a Christian, like Paul in Romans 7, when God’s perfect law becomes the standard and not “how much I’ve improved over the years”, I realize that I’m a lot worse than I fancy myself to be. Whatever I think my greatest vice is, God’s law shows me that my situation is much graver: if I think it’s anger, the law shows me that it’s actually murder; if I think it’s lust, the law shows me that it’s actually adultery; if I think it’s impatience, the law shows me that it’s actually idolatry (read Matthew 5:17-48).
We’ll always maintain a posture of suspicion regarding the radicality and hilarity of unconditional grace as long as we think we’re basically OK. Our presumption of “okayness” leads to a self-deception that robs us of the joy of our salvation and the undomesticated freedom that Christ paid so dearly to secure for sinners like me.
Martin Luther shows how probing the problem of presumption is and reveals that our so-called progress may not be as impressive as we think it is:

Presumption follows when a man sets himself to fulfill the Law with works and diligently sees to it that he does what the letter of the Law asks him to do. He serves God, does not swear, honors father and mother, does not kill, does not commit adultery, and the like. Meanwhile, however, he does not observe his heart, does not note the reason why he is leading such a good life. He does not see that he is merely covering the old hypocrite in his heart with such a beautiful life. For, if he looked at himself aright–at his own heart–he would discover that he is doing all these things with dislike and out of compulsion; that he fears hell or seeks heaven, if not also for more insignificant matters: honor, goods, health; and that he is motivated by the fear of shame or harm or diseases. In short, he would have to confess that he would rather lead a different life if the consequence of such a life did not deter him; for he would not do it merely for the sake of the Law. But because he does not see this bad reason, he lives on in security, looks only at the works, not into the heart, and so assumes that he is keeping the Law of God well. (Luther’s Works, St. Louis edition, 11:81 ff)

The Heidelberg Catechism also puts things in perspective:

Question 62: But why cannot our good works be the whole, or part, of our righteousness before God?

Answer: Because, the righteousness which can be approved of before the tribunal of God, must be absolutely perfect, and in all respects conformable to the divine law; and also, that our best works in this life are all imperfect and defiled with sin.

“At the cross”, says Gerhard Forde, “God stormed the last bastion of the self, the last presumption that you were going to do something for him.” Genuine freedom awaits all who stop trusting in their own work and start trusting in Christ’s work.
Tullian Tchividjian