Genesis 15:18
God made this with Abraham and his descendants
Which most of the world will argue includes folks besides just Jews who claim to come from Issac
He had another son Ishmael that comes to mind
Ishmael was Isaac’s half-brother and not an heir of Abraham. None of Abraham’s children from Keturah were heirs of Isaac’s stature either. It’s true that the lost ten tribes also have a claim to the land, but they still don’t know who they are.