Why is this term, "law," so repulsive? Law implies authority, and human nature likes no authority over it, even if the law expresses the authority of God and defines love. It is especially interesting that Paul says we will be judged according to what we actually know. Know of what? The law of God. The good works he mentions earlier include the works of keeping the law. Obviously, it is God's will that we live moral lives. Morality must have standards, or there is no such thing as morality. Laws define morality. We will be judged against what we know of the laws of God. Thus, he says in verse 13 that the doers of the law will be justified.
Despite what these verses say, theologians attempt to justify their "no-law" theology by claiming that Paul writes here of the natural man, not converted people. While partially true, it avoids the fact that this epistle was written to a church of God congregation (Romans 1:1-7) and that Paul repeatedly uses the personal pronoun "you"—as in "you are inexcusable, O man, whoever you are who judge" (Romans 2:1). This usage, combined with the fact that it is written to a church of God congregation, easily catches the converted in its purview.
In addition, it also avoids the fact that one reason God gives His Holy Spirit is to lead us into all truth (John 16:13). This includes the truth regarding morality, lawkeeping, and good works. As God leads us to greater depths of knowledge and understanding of His truth, it builds in us a more responsible knowledge of God's will. This raises the stakes in judgment because "to whom much is given, from him much more will be required" (Luke 12:48). Growth results in closer scrutiny against a higher standard of morality.
In the broader context of Romans, it becomes clear that each person—Jew or Gentile, converted or unconverted—is judged against what he knows, and God holds him responsible for working to produce obedience at that level. This is similar to what teachers expect of school children. They hold children in the higher grades more responsible for knowing and doing than those in lower grades. Courts use the same general system, holding adults more responsible for their crimes than children. Thus, for the same crime, an adult will receive a sterner punishment.
The called must realize that, because of their calling, the requirements—and thus the judgments—are much stiffer since they know so much more. This is why Paul says in Romans 3:31, "Do we then make void the law through faith? Certainly not! On the contrary, we establish the law." Faith upholds law or makes it firm because the law points out what righteousness, love, and sin are, and guides us in how faith is to be used.