What was God's purpose for Israel from the Abrahamic Covenant onward?
From the Abrahamic Covenant onward, God set Israel apart to receive the Law and the Temple. In His sovereign plan, He intended to use Israel to reach back into the ungodly river of humanity and bring them knowledge of the God of Abraham, Isaac, and Jacob, though Israel did not believe.
Les explains that from Genesis chapter 12 until the Book of Acts, God was dealing with the Jew only, with very few exceptions. The Abrahamic Covenant began His dealing with the nation of Israel, giving them the Law and the Temple. The idea was that one day God would funnel them back into that filthy, ungodly river of humanity and bring them a knowledge of the God of Abraham, Isaac, and Jacob. That was the noble plan of God in His sovereignty, but it did not work because Israel did not believe it. Les also places this within Old Testament history, noting Moses gave Israel the Law around 1500 B.C., and later David, Solomon, and Solomon's Temple appear around 1000 B.C., with the Temple standing only about 350-400 years.