If you belong to Christ, then you are Abraham’s seed, and heirs according to the promise.Galatians 3:29 NIV
Genesis records a number of times where God appeared to Abraham and made a promise to him. This promise takes a variety of forms, but they all point to the same thing. Abraham will become a great nation and will be a blessing to all people (Gen. 12:1-3). The land where he dwelt would be his forever, with countless descendants (Gen. 13:15-16). Offspring as countless as the stars (Gen. 15:5). And an everlasting covenant, established through Isaac (Gen. 17:1-22). Abraham was going to be the father of a great host.
But who are the heirs of that promise to Abraham? Who are the members of that great host? Is just it limited to his physical heirs? In Galatians 3:26-29 Paul makes the claim that the heirs to the promises made to Abraham are more than those who can trace their physical linage back to Abraham. Instead, all those who are in Christ, regardless our ethnic background or heritage, are Abraham’s children and heirs of those promises.
God worked through Abraham’s physical family until the coming of Jesus, the promised seed of Abraham (Gal. 3:16). Jesus was the offspring promised to Abraham that would inherit the promises. And those of us who are in Christ also experience the blessings of that promise. We are children of Abraham. It does not matter if you are Jew or Gentile, slave or free, male or female. In Christ we are all one. And the story of Abraham is now our story as well. And the promises made to him are applicable to us as well.