How Will Gentiles Be Included in the Restored, True Israel?

The Old Testament makes clear that Gentiles will be blessed in the time of the restoration of Israel from exile. However, to what degree and in what way the Gentiles will be included isn't as clearly revealed in the Old Testament as it is in the New. What does Scripture teach is the relationship between Israel and the church and the inclusion of the Gentiles in the new covenant era?

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