This prophecy is couched in formal parallels defining the conspiring kings. They are identified by their nation, by their capital city, and then as individuals. The effect of formally delineating their right of rulership is to place the prophecy in an official context. Just as it is an undisputed fact that Rezin (Rezon in non-biblical documents) rules in Damascus, and another that Pekin rules in Samaria, the prophecy positioned between these two true statements is also true.
That prophecy predicts the destruction of Ephraim as a people or nation within sixty-five years. Isaiah counsels Ahaz to believe it or else he himself will “not be established.” Isaiah does not explain the correlation between Ahaz’s belief and his own political survival. Nevertheless, Hezekiah, his son, would rebel against the domination by Assyria his father had allowed. In 701 B.C. Assyria invaded Judah and subjugated every city except Jerusalem itself.