Charles Ellicott Commentary Romans 9:31

"but Israel, following after a law of righteousness, did not arrive at [that] law." — Romans 9:31 (ASV)

Israel, on the other hand, though ostensibly pursuing a law whose object was righteousness, did not attain to such a law. They tried to keep the Law, but failed to keep it, and to bring themselves under its protection. The second “righteousness” is omitted in the best manuscripts.