God has not failed to keep His promises, even to the Jews, as there are those who have been and will be saved. This salvation is given by grace alone and is always part of God's sovereign will.
God: The Promise Keeper (v1-5)
Paul is an example of God's faithfulness in keeping His promises
The remnant is an example of God's faithfulness in keeping His promises
God: The Giver of Salvation (v6-10)
Salvation is only obtained by the grace of God
Salvation is given according to God's sovereign will