Acts 3:25 states, “And you are heirs of the prophets and of the covenant God made with your fathers. He said to Abraham, ‘Through your offspring all peoples of the earth will be blessed.’”  This promise was given to Abraham in Genesis 22:18 and again to his son Isaac in Genesis 26:4. The original covenant God gave to Abraham in Genesis 22:15-18 is unilateral, and applies to the entire human race.  In verse
17 God tells Abraham that he will make his descendants as numerous as the stars in the sky and as the sand on the seashore. The “seed as the stars” we believe refers to the heavenly seed of Abraham, Christ and the Church.  This spiritual
portion of the seed was hidden until God’s due time—at Jesus’ first advent. Jesus was the first seed, the Captain or forerunner. These “stars” are the “heirs” of Galatians 3:29 and 1 Corinthians 15:41-42. Abraham's spiritual seed as well as his earthly seed, the nation of Israel (the sand), will be the channel through which all the nations of the earth will be blessed. However, before such blessings can take place, the nation of Israel will have accepted Jesus as her Messiah.

Galatians 3:16 says, “The promises were spoken to Abraham and to his seed. The Scripture does not say ‘and to seeds,’ meaning many people, but to your seed, meaning one person, who is Christ.” Verses 17-25 of Galatians tell us that the Law given to the Jews did not set aside the Abrahamic covenant (vs. 17). The Law (the Hagar covenant mentioned in Galatians 4:24) was added because of transgressions until the Seed of Promise (Christ) came (vs. 19).  The Apostle Paul says that the Law was put in place to lead the Jews to Christ so that they could be justified by faith (vs. 24). “Now that faith has come, we are no longer under the supervision of the law.” (Galatians 3:25) Had the Jews accepted Jesus as their Messiah at his
first advent, they would have made up the vast majority of the heavenly seed. Since they did not accept Jesus, the call to be part of the heavenly class went out to the Gentiles from all nations.
 
As we derive from the above scriptures, the covenant God made with Abraham is all-inclusive and not contingent upon acceptance of Christ now. However, Jew and Gentile alike will all have to accept Christ before each can attain everlasting life on earth in the future.

We know that a great time of trouble awaits Israel and the world. Even though Israel has not recognized Jesus as their Messiah, God, nonetheless, holds a special place in his heart for the Jewish people because of their forefathers. At that time, in their distress, God will “fight’ for Israel as in the days of old. The Ancient Worthies (Abraham, Isaac, Jacob, Moses, David, etc.) will then come forth from their graves to lead and instruct the nation.

Then the hearts of the Jewish people will be turned to their God. “The time is coming,” declares the LORD, “when I will make a new covenant with the house of Israel and with the house of Judah. It will not be like the covenant I made with their forefathers when I took them by the hand to lead them out of Egypt, because they broke my covenant, though I was a husband to them,” declares the LORD. (Jeremiah 31:31-32) “A new heart also will I give you, and a new spirit will I put within you: and I will take away the stony heart out of your flesh, and I will give you a heart of flesh. And I will put My spirit within you, and cause you to walk in
My statutes, and ye shall keep Mine ordinances, and do them. And ye shall dwell in the land that I gave to your fathers; and ye shall be My people, and I will be your God." (Ezekiel 36:26-28) Then Israel will truly be the first of the earthly seed, a nation of blessings, unto which all the families of the earth will flow. “This is what the LORD Almighty says: ‘In those days ten men from all languages and nations will take firm hold of one Jew by the hem of his robe and say, “Let us go with you, because we have heard that God is with you.”’ (Zechariah 8:23)