His people already are a nation, Mt 21's vineyard parable. They are already in "one place" in Christ. The OT passages are useful, but must be informed by NT quotes of them, and they are not geographic.
That is simply not the case.
Throughout Matthew, Mark, Luke, John, Early Acts, and Hebrews thru Revelation, the premise is Genesis through Malachi (even in light of the rearrangement of the Hebrew Canon some passage in said NT make obvious are a later rearrangement of the Hebrew canon).
Throughout Matthew, Mark, Luke, John, Early Acts, and Hebrews thru Revelation, its readers, just as the immediate audience they depict, are ever reminded that "this is that which" this or that other OT Prophet wrote of, spoke, said, etc.
The actual history is built into the Hebrew theology. That is where this is to be studied out in. Not in "doing the history" in endless books by men who long ago parted from Isaiah 8's:
20. To the law and to the testimony: if they speak not according to this word, it is because there is no light in them.
The actual history is built into the Hebrew theology - its past is there, its present ever was, and its future ever is, and all three are ever consistently being referred back to within the above NT books.
"This is that.... Moses said this, Isaiah said that, the Psalmist had pointed to..." and on, and on, and on...
"To the law and to the testimony: if they speak not according to this word, it is because there is no light in them."