Romans 11:5-7, 23-24, 28-32

So too at the present time there is a remnant, chosen by grace. But if it is by grace, it is no longer on the basis of works; otherwise grace would no longer be grace. What then? Israel failed to obtain what it was seeking. The elect obtained it, but the rest were hardened

And even they, if they do not continue in their unbelief, will be grafted in, for God has the power to graft them in again. For if you were cut from what is by nature a wild olive tree, and grafted, contrary to nature, into a cultivated olive tree, how much more will these, the natural branches, be grafted back into their own olive tree.

As regards the gospel, they are enemies for your sake. But as regards election, they are beloved for the sake of their forefathers. For the gifts and the calling of God are irrevocable. For just as you were at one time disobedient to God but now have received mercy because of their disobedience, so they too have now been disobedient in order that by the mercy shown to you they also may now receive mercy. For God has consigned all to disobedience, that he may have mercy on all.