Why did God promise that all nations would be blessed in Abraham's seed?
Abraham obeyed God's voice, kept His charge, commandments, statutes, and laws, and therefore God promised that all nations would be blessed in his seed. The blessing would flow through Abraham's descendants, particularly the nation of Israel, to whom God committed His Word, so that all nations could be reached.
Les explains that the Abrahamic Covenant includes the promise, 'in thy seed shall all the nations of the earth be blessed.' The reason given in the text is that Abraham obeyed God's voice and kept His charge, commandments, statutes, and laws. Les also addresses the question of how God can speak of 'nations' while dealing with Israel: everything must come through this one little nation, because 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 or the Word of God. This uniqueness of Scripture allows the blessing to reach all nations. In the surrounding context, Les notes that Abraham and Isaac were still dwelling among the Canaanite tribes, not yet possessing the whole land, but God promised a coming day when they would have it.
And I will make thy seed to multiply as the stars of heaven, and will give unto thy seed all these countries; and in thy seed shall all the nations of the earth be blessed;
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