Do not be arrogant toward the branches [of natural Israel]. If you are, remember it is not you who support the root, but the root that supports you.
Romans 11:18 ESV

Never look down on the native branches, even in their unfaithfulness. They remain chosen for a purpose, and God is eagerly awaiting their repentance so that he may restore them to the tree.

Without God’s faithfulness to the patriarchs of Israel, we would have no hope. The New Covenant that brings ultimate forgiveness and eternal salvation was only given to the houses of Israel and Judah. There is no Gentile people--no non-Israelite “church”--included.