Why did Israel, who pursued the law of righteousness, fail to attain it?
Israel failed because they sought righteousness by the law rather than by faith. They could not believe what God said, while Gentiles who heard Paul's preaching believed and attained righteousness. Scripture's absolute stands: without faith it is impossible to please Him.
Les explains that Israel had come out of dark idolatry and paganism, but they could never understand the glorious light of God's grace. Gentiles, who had not been following after righteousness, attained it because they had faith. Israel's problem was that they could not believe what God said; they sought righteousness not by faith, but by the law. Les points to two absolutes: without the shedding of blood there is no remission, and without faith it is impossible to please Him. He adds that much of Christendom today is not that different.
But Israel, which followed after the law of righteousness, hath not attained to the law of righteousness.
Wherefore? Because they sought it not by faith, but as it were by the works of the law. For they stumbled at that stumblingstone;