In "Doctrinal Discussion" Don Callaway writes:

At the center of this lesson lie two questions: The first is the broader question of the Church's relationship with Israel, and more specifically, whether Old Testament promises to Israel apply to the Church today. Second, if these verses do apply to the Church, at what point should we expect these promises to be fulfilled? Two general approaches have been taken in addressing the relationship between Israel and the Church. Replacement Theology teaches that the Church has replaced Israel, and therefore is heir to all her promises and blessings. A second approach understands the Church to exist as a separate organism from Israel and therefore has no claim to her promises. This approach would prevent the New Testament Church from appropriating many Old Testament promises, including the ones provided here in Isaiah 62. If pushed to an extreme it might also lead to the faulty conclusion that Israel is under a sep-arate salvation plan than the Gentile Church. What do the Scriptures say?

Source: Building Christian Relationships: Adult Teacher's Insights, page 13.