Isaiah 7:17
17The LORD will bring on you, on your people, and on your father’s house days that have not come, from the day that Ephraim departed from Judah, even the king of Assyria.
Arminian
The LORD will bring on you, on your people, and on your father’s house days that have not come since Ephraim departed from Judah, even the king of Assyria. Wesley: although God will deliver you at this time, yet He will requite all your wickedness. Part of the storm in Ahaz’s reign; the rest on sons and successors. The king is their plague, the rod of God’s anger (10:5).
“Bring”—a deliverance now, and a requital. Assyria is historic, the ally they ran to (7:9).
Reformed
Calvin: what Ahaz hopes will be his preservation—the Assyrian—will be utterly destructive to him. He might have remained at ease and received God’s help; he chose to call them in. Family of David not exempt. God regulates judgments so as to spare His Church and not let the wicked mixed with the good escape. Amidst the most dreadful deaths the Church remains safe.
The hired help is the judgment. No dispute here: upon you, your people, father's house, Ephraim’s departure, king of Assyria.