Matthew Poole and continuators on Isaiah 19:24

24 In that day shall Israel be the third with Egypt, and with Assyria , even a blessing in the midst of the land :

The third Party, to wit, in that sacred League, whereby all of them oblige themselves to God.

These People are named, because they were the most obstinate and malicious Enemies to God's Church, and therefore in a special manner accursed by God; but they are here put Syncchdochically for all the Gentiles.

This is peculiar to Israel, who is not onely a third Party, as the others are, but is the most eminent and blessed of the three, as being the Fountain, or rather the Conduit-pipe, by which the Blessing is conveyed to the other two, because Christ was to be born of them, and the Gospel-Church and Ordinances were first established among them, and from them derived to the Gentiles.

Or, of the earth. Which may be added, to imply, that God's Blessing should be convey'd from and by Israel, not onely to the Egyptians and the Assyrians, but to all the Nations of the Earth, in the midst of which the Land of Israel might well be said to lie. Or, of that land, of which I am here speaking; or, the Singular Number being put for the Plural, of those lands, Egypt and Assyria, between which Israel lay.