The phrase “bait and switch” refers to the unscrupulous practice of advertising one item and selling an inferior product in its place. Paul’s Jewish readers may have felt that they had been victims of a kind of spiritual bait and switch when they read that the circumcision practiced under the Law of Moses was merely outward and physical (v. 28). Such a claim would have raised an obvious question: was there any advantage to being a Jew? Paul’s answer was a clear, emphatic “yes.”
The chief advantage of the Jews was that they had been given the Word of God. While the law exposed humanity’s problem of sin, it also pointed to God’s solution for sin. The rites and sacrifices of the law foreshadowed Jesus Christ’s once-for-all offering of Himself on the cross. Indeed, the author of the book of Hebrews referred to the Law of Moses as a “shadow” of the good things to come in Christ (Heb. 10:1).
If the law could not save, why was it given? For one thing, it made clear that there was no alternative other than the grace of Christ. This wasn’t a weakness in the law but rather in us. Sin kept those who had received it from meeting its high standard. The Jews’ inability to bear the yoke of the law was proof that both Jews and Gentiles alike were all under sin (v. 10; cf. Acts 15:10). The primary function of the law was to highlight the universal sinfulness of mankind and to leave men and women without excuse. Once the law was given no one could stand in God’s presence and say, “If you had only told me what had been expected of me, I would have complied.”
Some still misunderstand the message of God’s Law. They believe they can earn God’s favor through religious practices and good works. While these may be admirable, they are not enough to expunge the guilt of sin. No one can be justified in God’s sight by these things.