Having finally completed Thomas Schreiner's The Law and Its Fulfillment: A Pauline Theology of Law (I started this en roue to Africa in October!), this afternoon I've tried to summarize Schreiner's position in a series of "theses." Schreiner does not do this himself, although much is summarized in the conclusion of the book. So, these should be read as my interpretation of Schreiner, not direct quotations (although, there are a lot of direct quotations in what follows).
1. The term law (nomos) in Paul usually refers to the Mosaic law and in particular the commandments of the law, although Paul also uses the term law metaphorically at times in reference to some other principle or order or power.
2. The term works refers to deeds that are performed, while the phrase works of law refers to the works or deeds demanded by the Mosaic Law including the moral and ethical commands. Works of law may include but is certainly not limited in its scope to distinctively Jewish ceremonial laws (circumcision, Sabbath, food laws) which functioned as “boundary markers.”
3. Paul’s primary critique of Judaism is not that it is nationalistic and exclusive of Gentiles, nor is his primary concern with works of law that they are legalistic, although there is good evidence that Paul was countering legalism in his disputes with Judaizers. At the heart of legalism is the delusion that human beings are good and that their works can be sufficient to obtain righteousness.
4. But the primary reason why Paul asserts that no one can be saved by the works of law is because no one can obey the law perfectly because of sin. Paul believes that people would be saved if they could perfectly keep the law, but this is impossible. Therefore, a right standing with God comes only through faith in Jesus Christ.
5. One reason the law does not save is because a salvation-historical shift has occurred with the coming of Jesus Christ. When Paul says the law was a pedagogue or guardian, he is emphasizing its temporary and provisional nature. The Mosaic covenant was not intended to be in force indefinitely, but only for a certain period of history, as an interim measure until the promise given to Abraham was fulfilled. That promise was fulfilled in Jesus Christ.
6. The purpose of the law was not to save, but to increase sin. Though the law itself is good, it has no inherent power to produce the obedience it requires. Because of the weakness of the flesh, the law without the Spirit only produces condemnation and death. The triumph of grace over sin shines brighter when the full depth of human sin is realized. Human beings do not realize the extent and gravity of their corruption until they measure themselves against the standard of the law.
7. There is a tension in the New Testament between the abolition of the Mosaic law and the fulfillment of the Mosaic law. The relationship between the law and believers today is complex. We should avoid radical discontinuity on one hand, which denies that the moral norms expressed in the Old Testament law are in force for believers today. But on the other hand we should also avoid radical continuity which asserts that the cultic laws of Israel should continue to be practiced or which attempts to impose the civil laws of Israel onto civil governments today. There are clear indicators in the New Testament that the ceremonial and cultic aspects of the Mosaic law (sacrifice, food laws, circumcision, Sabbath, purity laws, feasts and festivals) have been fulfilled in Christ. Yet New Testament authors do not hesitate to appeal to the Old Testament in their moral and ethical exhortations for Christian living.
8. Good works are not the basis of a person’s justification, because no one can obey God’s law perfectly. The substitutionary and atoning death of Jesus Christ is the only sufficient ground for justification. Yet, all who are justified are given the gift of the Holy Spirit and will produce obedience that is significant, substantial, and observable, and final judgment and the granting of eternal life will be in accordance with these Spirit-empowered “good works.”
The whole issue of law/gospel is a particularly thorny one that I've been wrestling with (on and off) for several years. I'm still not completely satisfied and don't feel like I've fully digested all that I've read from Schreiner, Westerholm, and others. But this is an important issue because it influences so many others, especially one's doctrine of justification. My thinking has definitely been challenged and influenced by what Schreiner has written. I hope that with further reading on this issue, and especially further and more in-depth study in Paul's letters themselves, will yield increasing clarity in the years to come.