Rom 10:2-4
"For I bear them witness that they have a zeal for God, but not according to knowledge... For Christ is the end of the law for righteousness to everyone who believes."
Israel’s problem is not lack of religiosity — it is zeal without knowledge (kat epignosin). Christ is the telos of the law — the goal, fulfillment, the end toward which the law always pointed.
Rom 10:9-13
"If you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved... for everyone who calls on the name of the Lord will be saved."
The formula of salvation: belief in the heart + confession with the mouth. The confession 'Kyrios Iesous' was the most radical declaration in the Roman world, where 'Kyrios Kaisar' was the loyalty demanded.