In Romans 9-11, Paul answers perceived Jewish objections to God's rejection of the nation of Israel. He explains the sovereignty of God, including God's choice on how man is saved. While the Jews sought to be righteous by the works of the Law of Moses, more fundamentally their flaw was simply refusing the plan God had authored. We could be guilty too, even if we refuse to subscribe to a merit based plan. God's grace is often perverted, and if it is, then "grace is no longer grace" (Romans 11:6).