It seems that Paul’s main purpose in this passage of Scripture is to show that God’s chosen people are not limited to a certain physical lineage. While that is true today, it was also true at other times in the past, as in the case of Jacob being chosen over Esau. While God has chosen certain people through which to accomplish His purpose throughout time, we know from Acts 10:34 that God is no respecter of persons with regards to salvation.
Yes, I think you've got it. For Moses, Samuel, Jacob and and others Free Will wasn't free. God had ordained their faith and much of what would happen in their lives.
The passage I gave you, talks about God's choice of Jacob before he was born, just as I said.
God chose Jacob and that blows the doctrine of Free Will. And thereby opens the question of how God instilled faith in Jacob according to His determination.
Good bye for now.