How can the Law be for Israel but cover the whole human race?
The Law was given only to the nation of Israel, never to the Gentiles, yet as Romans 3 shows, it nonetheless covers the whole human race. Israel received it as part of their heritage, but its scope extends to all humanity, while the Law as such remains Israel's alone.
Les explains that the Law was given exclusively to the nation of Israel, never to the Gentiles. It included the Ten Commandments, rituals, civil regulations, priesthood stipulations, and instructions for the tabernacle, later Solomon's Temple, all part of Israel's heritage. Yet, as seen repeatedly in Romans chapter 3, even though the Law was given to Israel, it covers the whole human race. The Law as such, however, was given only to Israel, and that distinction must never be lost.