What does Romans 3:3 mean?

Paul is staging a question-and-answer session between himself and an imagined critic of his words in chapter 2. Now he asks the next logical question: "What if some were unfaithful?" By this, Paul seems to be pointing to what he said in the previous chapter. The Jewish people were given God's law, but they did not keep it. As a nation and as individuals, every Jewish person had sinned. Nobody can keep the law perfectly, and even those who had been "entrusted with the oracles of God" (Romans 3:2) were not immune to sin.

Paul's questioner follows by asking, does the unfaithfulness of some of the Jewish people nullify God's faithfulness to His people? Does their sin make His faithfulness pointless? In other words, does the fact that those under the law broke the law, that they sinned as all people do, mean that God will no longer be faithful to them?

In the following verse, Paul will answer this question with a loud and emphatic "no."