i’ve answered this question and posted on it in detail, you need to study history snd the migration of the ancient israelites or you can identify to whom the the apostles were writing to, better yet search for a map of the churches that the apostles had established prior to AD 70, or ask yourself who received the gospel and built the greatest nations in history founded on Christ Jesus , which people received the gospel and as prophecied spread to the east and the west, north and south establishing mighty nations whatever they’ve gone. God has kept his promises to abraham, he kept his promises to jacob and to joseph, he has raised up the true israel of God over all the nations of the earth as a peculiar people, meanwhile the heathen are still rolling around in dust, living in poverty and desolation reaping the reward of their false gods, it’s obvious to anybody who is being honest with themselves who the sheep nations are as opposed to the gost nations
It seems you are saying then the true Israel are the first century believers and all believers through the ages which I would agree, Galatians and the book of Hebrews make this clear.