Romans 10:1-4 refutes the idea that Jews can be saved apart from Jesus: Paul's heart's desire is that his Jewish kinsmen be saved — meaning they currently are not — despite their genuine zeal for God.

Romans 10:1-4: Paul bears witness they have a zeal for God but not according to knowledge; being ignorant of God's righteousness they seek to establish their own self-righteousness. 'Christ is the end of the law for righteousness to everyone who believes.' Mike notes these are Jews who have heard the gospel, not pre-Christ Jews who never encountered it.