Scripture reveals this mediator

I will put enmity between you and the woman, and between your offspring and her offspring; he shall bruise your head, and you shall bruise his heel."

I will bless those who bless you, and him who dishonors you I will curse, and in you all the families of the earth shall be blessed."

and in your offspring shall all the nations of the earth be blessed, because you have obeyed my voice."

The scepter shall not depart from Judah, nor the ruler's staff from between his feet, until tribute comes to him; and to him shall be the obedience of the peoples.

"Behold, the days are coming, declares the LORD, when I will raise up for David a righteous Branch, and he shall reign as king and deal wisely, and shall execute justice and righteousness in the land. In his days Judah will be saved, and Israel will dwell securely. And this is the name by which he will be called: 'The LORD is our righteousness.'

Who is a God like you, pardoning iniquity and passing over transgression for the remnant of his inheritance? He does not retain his anger forever, because he delights in steadfast love. He will again have compassion on us; he will tread our iniquities underfoot. You will cast all our sins into the depths of the sea. You will show faithfulness to Jacob and steadfast love to Abraham, as you have sworn to our fathers from the days of old.

To him all the prophets bear witness that everyone who believes in him receives forgiveness of sins through his name."

Long ago, at many times and in many ways, God spoke to our fathers by the prophets,

For if you believed Moses, you would believe me; for he wrote of me.

For since the law has but a shadow of the good things to come instead of the true form of these realities, it can never, by the same sacrifices that are continually offered every year, make perfect those who draw near. Otherwise, would they not have ceased to be offered, since the worshipers, having once been cleansed, would no longer have any consciousness of sins? But in these sacrifices there is a reminder of sins every year. For it is impossible for the blood of bulls and goats to take away sins. Consequently, when Christ came into the world, he said, "Sacrifices and offerings you have not desired, but a body have you prepared for me; in burnt offerings and sin offerings you have taken no pleasure. Then I said, 'Behold, I have come to do your will, O God, as it is written of me in the scroll of the book.'" When he said above, "You have neither desired nor taken pleasure in sacrifices and offerings and burnt offerings and sin offerings" (these are offered according to the law), then he added, "Behold, I have come to do your will." He does away with the first in order to establish the second. And by that will we have been sanctified through the offering of the body of Jesus Christ once for all.

For Christ is the end of the law for righteousness to everyone who believes.

But when the fullness of time had come, God sent forth his Son, born of woman, born under the law, to redeem those who were under the law, so that we might receive adoption as sons.

These are a shadow of the things to come, but the substance belongs to Christ.