I don’t know where you get your verses from, but my version of Numbers 9 has only 23 verses.
Oh–I see it is Romans 9:30-31.
Paul is setting out his understanding of the Gospel in Romans, He starts by distinguishing and comparing the Jews, with the Law, and the Gentiles, who do not have the Law. He needs to show the Law is good, but limited, while Faith is what allows us to receive salvation.
So he shows how the Law shows us where our sin lies–but is not strong enough to go beyond sin. Does that mean the Law, which leaves us in evil, is evil? No–it’s just not enough by itself. Hence, “Israel, who pursued the law of righteousness, did not attain to that law” (it’s a rhetorical question). But now, in Christ Jesus, Israel can attain the law, and salvation–if they wish. Paul himself is an example, if not a common one.
But the Gentiles–since they do not have the law–if they rely on Jesus at all, they rely on faith from the start and so attain righteousness in Jesus. They don’t have the too-limited good of the law to distract them, as it distracted Paul for so long.
He will go on to show how the Jews will stumble over the law, once they discover their effort and works are not enough–and, like Paul himself, that will be the moment that Jesus can show them the better way they need.