Was Abram’s Blessings and Promise for Everyone?
Genesis 12:3 (ESV) … “I will bless those who bless you, and him who dishonors you I will curse, and in you all the families of the earth shall be blessed.”
In the midst of the seven “I wills” of God for Abram, there is a promise of blessing that goes so far beyond these material promises that it deserves to be considered by itself. It is a second prophecy of the coming of Jesus Christ. Following Adam and Eve’s fall, the first messianic prophecy occurred in the midst of God’s judgment on Adam, Eve, and the serpent. In it God said to the serpent, “I will put enmity between you and the woman, and between your offspring and hers; he will crush your head, and you will strike his heel” (Gen. 3:15). In this second prophecy, God speaks of the work of the Deliverer not so much as a conquering of Satan and a defeat of his works as a spiritual blessing to come on all peoples of the earth. It is a potent but brief statement: “All peoples on earth will be blessed through you” (Gen. 12:3).
How did Abram react to this promise? We are not told of any specific reaction to this part of God’s total revelation to him, but we can imagine that Abram’s reaction was similar to David’s when David was told that God would build him a house and that a descendant of his would sit on his throne forever. David marveled and said, “Is this your usual way of dealing with man, O Sovereign Lord?” (2 Sam. 7:19). David knew that what the Lord was promising was not possible for mere human beings and must therefore involve the coming of the Messiah. Abram also must have perceived God’s promise of blessing to the nations to be in this category.
God had said, “I have given you many material blessings, including a land of your own, descendants that will increase to be a great nation, fame for you, and the promise of future blessing and prosperity. But this is not enough. In addition to these physical blessings, I am going to distinguish you with a spiritual blessing that will overflow from you to all the families of the earth.” Abram, who was no dunce in spiritual things, must have reasoned, “If all the families of the earth are to be blessed through me, then this blessing must not depend on me as an individual, since I will not live to see those human families. Besides, I need blessing myself and cannot be the source of my own blessing. This promise must refer to one who will be born from my posterity. He will be greater than I am, since he will be a source of blessing himself. He must be God and not a mere human being, though he will have to take a human body and nature so that he will truly be my seed.”
Because of this reasoning, Luther felt that the promise of God in Genesis 12:3 foretold not only the redemption of the race but even the incarnation of Jesus. He said that it should be written “in golden letters and should be extolled in the languages of all people,” for “who else … has dispensed this blessing among all nations except the Son of God, our Lord Jesus Christ?”
 Boice, J. M. (1998). Genesis: an expositional commentary (pp. 450–451). Grand Rapids, MI: Baker Books.