Why did God promise that all nations would be blessed through Abraham's seed in Genesis 26?
Scripture grounds the promise in Abraham's obedience: he obeyed God's voice and kept His charge, commandments, statutes, and laws. God also chose to channel blessing to all nations through Abraham's seed, Israel, the nation through whom He would commit His Word, so the whole world could be blessed.
Les explains that the promise in Genesis 26—'in thy seed shall all the nations of the earth be blessed'—is part of the Abrahamic Covenant and rests on the reason given in the text: 'because Abraham obeyed my voice, kept my charge, my commandments, my statutes, and my laws.' Even though God is dealing with Israel, He can speak of all nations because everything must come through that one little nation. Les notes that every word of the Book came out of Israel; all the writers of Scripture were Jews, and Paul makes this plain in Romans 3, where the advantage of the Jew is that unto them were committed the oracles of God. This makes the Book unique. The promise also looks ahead: Abraham and Isaac were still dwelling among the Canaanite tribes and did not yet possess the land, but the day was coming when God would give it to them.
Sojourn in this land, and I will be with thee, and will bless thee; for unto thee, and unto thy seed, I will give all these countries, and I will perform the oath which I sware unto Abraham thy father;
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