Can Christians Claim Old Testament Covenant Promises?

A similar promise of physical blessings was made by God previously to Israel if they remained faithfully obedient to His covenant and also what the negative consequences were if they did not (Deut 28:1-6, 8, also Lev 26). The King of Israel and his people are to keep the covenant with God, and in doing so, He would bless them, even the very land of Israel itself.

The Old Testament is about Hebrews in ancient Israel who receive Old Covenant promises. The New Testament is about people receiving New Covenant promises. The book of John demonstrates that the promises and blessings given to New Covenant people, those who are Born-Again, are fulfilled in Jesus Christ, who is the better Temple, people, sacrifice, high priest, etc. God made the New Testament Covenant that builds upon the Old Testament covenants, which were given to different peoples of God that were dealt with differently by God.

There is some national application here for the followers of Jesus (those who are Born-Again) in all the nations in the world (165 at the time of writing) who reflect and live out the truth of 2 Chron 7:14 by walking daily in humility and repentance as they seek after God so that they can be His vessels and agents of reconciliation in order to bring His blessings into the world (see Heb 12:3-11).

It was at the Cross where Jesus died, and then was raised from the dead after three days, that the old covenant of Law passed away in its entirety, and every person who becomes Born-Again are then under the new Covenant of grace (Jer 31:31-34; Gal 3:15-4:7; Rom 6:14-15; 7:4-6; Heb 8:1-10:18). The Old Testament is still the Word of God, and along with the New Testament, they are the final authority as the infallible, inerrant Word that was divinely breathed out by God.

The Born-Again Christian is no longer under the requirements of the Law and stipulations of the old covenant (Jer 31:31-34; Ezek 36:26-27; 2 Cor 3:6; Heb. 8:8-13). They are grafted into the vine of Israel, the people of God, and become with them, "a chosen race, a royal priesthood, a holy nation, a people for his own possession" because they were once not His people, but, through Jesus Christ, they become "God’s people” (Rom 11:17-24; 1 Peter 2:9-10).

Jesus said that all 613 laws of the Old Testament (365 thou shalt not’s and 248 thou shalts, or thou ist in big troubleth!) depend on just two laws which are really one and the same, “You shall love the Lord your God with all your heart and with all your soul and with all your mind”… and “You shall love your neighbor as yourself” (Matt 22:37-40 ESV). The law all pointed to fulfillment in Jesus, and it still functions as a moral standard for every Born-Again Christian to live their life in the love of God (Rom. 13:8–10; Gal. 5:14; 6:2; 1 Cor. 9:20–21).

Out of all the nations on the Earth, God chose to covenant with Israel. They did not choose to covenant with God. Every person of that individual nation was required to repent just like every person in Nineveh, from the king down to all the citizens, and even all the animals, were required to wear sackcloth, fast and repent, which they did, and God spared them all. There has never been another nation in the history of the world or seen in the Bible that had a covenant with God.