Legalism & Self Help - The Fruit of Missing the Gospel

In Preaching the Whole Bible as Christian Scripture, one of the most important books on preaching I have ever read, Graeme Goldsworthy writes:

We are all legalists at heart. We all love to be able to say that we have fulfilled all kinds of conditions, be they tarrying, surrendering fully, or getting rid of every known sin, so that God might truly bless us. It is a constant temptation to want to take our spiritual pulse and to apply the sanctification barometer. . . . The preacher can aid and abet this legalistic tendency that is at the heart of the sin within us all. All we have to do is emphasize our humanity: our obedience, our faithfulness, our surrender to God, and so on. The trouble is that these things are all valid biblical truths, but if we get them out of perspective and ignore their relationship to the gospel of grace, they replace grace with law.

If we constantly tell people what they should do in order to get their lives in order, we place a terrible legalistic burden on them. Of course they should obey God; of course we should love him with all our heart, mind, soul, and strength. The Bible tells us so. But if we ever give the impression that it is possible to do this on our own, not only do we make the gospel irrelevant, but we suggest that the law is in fact a lot weaker in its demands than it really is. Legalism demeans the law by reducing its standards to the level of our competence.

[ . . .] In practical terms, if we as preachers lay down the marks of the spiritual Christian, or the mature church, or the godly parent, or the obedient child, or the caring pastor, or the responsible elder, or the wise church leader, and if we do this in a way that implies that conformity is simply a matter of understanding and being obedient, then we are being legalists and we risk undoing the very thing we want to build up. We may achieve the outward semblance of conformity to biblical pattern, but we do it at the expense of the gospel of grace that alone can produce the reality of these desirable goals. To say what we should be or do and not link it with a clear exposition of what God has done about our failure to be or do perfectly as he wills is to reject the grace of God and to lead people to lust after self-help and self-improvement in a way that, to call a spade a spade, is godless.