Who was God dealing with primarily from Abraham until Acts?
From Abraham until the book of Acts, God dealt primarily with the nation of Israel. This period shows Israel as the primary focus of God's dealings, though He did not forget the Gentiles; they could not be dealt with until Christ went to the cross.
Les explains that God was dealing primarily with the nation of Israel all the way from Abraham until the book of Acts. Even so, God did not forget about the Gentiles. He could not deal with them until Christ went to the cross, but He had not forgotten them. Les also connects this to Isaiah's prophecy about the root of Jesse, noting Jesse was David's father and Christ is considered the son of David, linking the line of Jewish kings. The prophecy that Gentiles would trust in Him has not yet happened, but it is going to.
Now I say that Jesus Christ was a minister of the circumcision for the truth of God, to confirm the promises made unto the fathers: