In Genesis 12:1-3 God proclaims His plan to bless all the nations. This promise is not just for Abraham and His descendants. It is for all God people! Throughout this we can see God’s consistency in that he has always had a plan for all the nations. It is not just a “New Testament thing”.
Through this promise, Israel was blessed to be a blessing; in the same way we are blessed as Christians to be a blessing to others. This means it is our duty as Abraham’s seed (through faith) to share our blessing with the nations. Through Christ in us the nations of the earth will be blessed.
Unlike many missions advocators today, I would like to argue that “The Great Commission” and “The Great Commandment” are not the strongest mandate for global mission. In fact this mandate is not only found in the New Testament! Rather, I would say that the entire story of the Bible, complete with promises, mandates, and examples is a strong and definitive mandate for global Mission. God’s promise to Abraham, when it is linked to biblical commands gives us a much more compelling mandate for mission than just the commands because it gives us a solid vision for God’s vision and our role in His ultimate plan; for us to be a part of blessing the nations.
God’s original promise to Abraham is fulfilled by Abraham’s seed in three different time periods by three different groups of people. In the past it was fulfilled by Abraham and his seed: the people of Israel. In the present, this promise is being fulfilled by Christ and His church. And in the future it will be fulfilled by the final destiny of all the redeemed! Thus since we are in the present, we can see that God’s promise of blessing upon all peoples will be fulfilled by those joined with Christ by faith because they inherit the hope and the promise of the blessing to Abraham and his descendants.