God chose the Jews to be the people through whom the rest of the world could find salvation. But this does not mean the entire Jewish nation would be saved. Only those who are faithful to GOD ( remnant) are saved and true to God. We are saved through faith in Jesus. Not because we are in a Christian family.
Do you think that you are saved because of your goodness? Do you think that God will not save someone who you don’t like and is very rude? Not at all. God loves everyone. Salvation is by grace and is a free gift from GOD. It cannot be earned in part or full. It can only be accepted with thankfulness and praise.
So let us in kindness continue to steadfast in perseverance in faith. Let steadfastness be the proof of the reality of faith and a by-product of salvation.