The universal depravity of our race is nowhere more evident than it is in the fact that we are all proud, self-righteous, legalists by nature. By nature all men cherish the foolish notion that we can, in some measure, atone for our sin and win God's favour by our obedience to his law, or by some other works of righteousness we perform. But it is all a vain delusion. It is this natural tendency toward self-righteousness and legalism that Paul constantly exposed and denounced. It was as common to the Gentiles as it was to the Jews. He declared as plainly to the Romans as he did to the Galatians, 'that a man is justified by faith without the deeds of the law' (3:28). He keeps insisting, in all his writings, that salvation is by faith alone, in Christ alone, that it might be by grace alone, without the works of human flesh. Paul opposed nothing so fully and constantly as he did legalism. And he opposed that in any form. He gave no place for the law in the house of faith (Read Galatians 4:21-31).
'Do' or 'Done'?
Why is the law/grace issue so important? The answer is obvious: Any mixture of law and grace is a total denial of grace (Romans 11:6). Almost all doctrinal error and religious heresy arise from man's inability to distinguish between the law and the gospel. Blessed is the man who knows the difference between grace and works, gospel and law. Very few do. The law says, 'Do.' The gospel says, 'Done!' That is the difference. Legalism always attempts to wear the mask of grace. But it always smells like works. The smell of the carcass is easily detected. Legalism will always enforce its claims, somewhere, with the promise of reward or the threat of punishment. It may talk about 'love' and 'faith'. But legalism must have its 'stick and carrot'. At some point the legalist will either promise or threaten something, conditioned upon man's obedience or disobedience. The gospel conditions everything on the Person and work of Christ alone!
Dead to the law!
Legalism is on the rise everywhere. And it comes under many names: Romanism, Liberalism, Fundamentalism, and even Reformed Theology. The legalist never says, 'We are saved by works alone.' The legalist says, 'Salvation is by grace alone, through faith in Christ alone, but...' And then he inserts some work or condition which man must add to the grace of God to make salvation complete. Legalism is always subtle. It is always an attempt to mix works and grace. The legalist may cry out vehemently, 'I am preaching grace!' But if it comes out sounding like works, looking like works, and smelling like works, it probably is works. In Galatians 2:19-21 Paul tells us three things which should prevent any who profess faith in the name of Christ from ever being led into legalism.