For Moses writes about the righteousness which is based on the law: “The man who does those things shall live by them.” But the righteousness which is based on faith says, “Do not say in your heart, ‘Who will ascend into heaven?’ ” (that is, to bring Christ down), or, ‘Who will descend into the deep?’ ” (that is, to bring Christ up from the dead). But what does it say? “The word is near you, in your mouth and in your heart.” This is the word of faith that we preach: that if you confess with your mouth Jesus is Lord, and believe in your heart that God has raised Him from the dead, you will be saved, for with the heart one believes unto righteousness, and with the mouth confession is made unto salvation. For the Scripture says, “Whoever believes in Him will not be ashamed.”

Romans 10:5–11

In the passage from the epistle to the Romans, Paul cites Deuteronomy 30. He is contrasting two points. Two important things that are relevant to understand.

This commandment which I am commanding you today is not hidden from you, nor is it far off. It is not in heaven, that you should say, “Who will go up for us to heaven and bring it to us, so that we may hear it and do it?” It is not beyond the sea, so that you should say, “Who shall go over the sea for us and bring it to us, so that we may hear it and do it?” But the word is very near to you, in your mouth, and in your heart, so that you may do it.
See, today I have set before you life and prosperity, and death and disaster. What I am commanding you today is to love the Lord your God, to walk in His ways, and to keep His commandments and His statutes and His judgments, so that you may live and multiply. Then the Lord your God will bless you in the land which you go to possess.

Deuteronomy 30:11–16

Knowing context, this portion of the text from Moses follows the prophecy he gave of Israel being scattered among the nations for their disbelief. It comes in the promise of restoration. It is not a promise of entering the land from the Exodus.

We who are alive today are a privileged people. We witness the beginnings of this restoration. The return of the Jewish people to their homeland is happening now. It is not a return after the Exodus because they hadn’t yet arrived to the Promised Land from the Exodus. This is a prophecy of both diaspora and a return from it. As astute readers and by virtue of being alive today, we are extended both the privilege to witness it and participate in it during our lives.

Being drawn by God Himself, these disbelieving Israelis will be gathered into the land. They will become the all Israel that is saved when they believe.

As the text in Deuteronomy declares, the idea of believing is not just for a future time and place. In verse 11, Moses tells them that the commandment to believe is available to any whom would have it. They don’t have to go anywhere to get it. They don’t have to wait for some future date to be saved. The word is in their mouth. In other words, salvation doesn’t come by what one does, keeping law, the sprinkling of water on babies, or listening to some pastor. Salvation comes by personal acknowledgment of Jehovah God. A Kinsman Redeemer Who died and rose again, and a personal profession in Him.

Which is exactly what Paul cited in Romans 10. As he is speaking to his Jewish brothers in Rome. He is juxtaposing the inadequate righteousness that comes by law keeping with the Gospel. Keeping law doesn’t save. Believing the Gospel does. That is, salvation doesn’t come by law-keeping. It comes by personal belief and profession issuing forth the “treasures of the heart.”

 But if your heart turns away, so that you do not obey, but are drawn away, and worship other gods and serve them, then I declare to you today that you will surely perish and that you will not prolong your days in the land which you are crossing the Jordan to go in and possess.
I call heaven and earth to witnesses against you this day, that I have set before you life and death, blessing and curse. Therefore choose life, that both you and your descendants may live; that you may love the Lord your God, that you may obey His voice, and that you may cling to Him, for He is your life and the length of your days; and that you may dwell in the land that the Lord swore to your fathers, to Abraham, Isaac, and Jacob, to give them.

Deuteronomy 30:17–20

There are consequences to not believing. Some are temporal, but the worst is eternal. One dies in their sins. That is why Paul encourages everyone to call upon the name of the Lord.

For there is no distinction between Jew and Greek, for the same Lord over all is generous toward all who call upon Him. For, “Everyone who calls on the name of the Lord shall be saved.”

Romans 10:12–13

The future of the world is Jewish. It will be ruled by a rightful Jewish King.