Isaiah 7:10-17

Yahweh confronts Ahaz HaMelekh (King Ahaz) and his fear of Ephraim and Damascus, for their alliance against Judah. It was only a few hundred years previous that Yahweh had confronted another commander's fear - Joshua. Joshua, however, had the benefit of his witness to see Yahweh's power and giving of Torah to give Him confidence and fuel his faith, where Ahaz had none.

Thus, Yahweh gives Ahaz the chance: "Ask of Me a sign! Let Me show My power to you! I will give you the confidence and faith in Me that I have demanded of you and all your fathers!" But Ahaz is true to his lack of faith and, in his fear, tries to cover it under the cloak of piety. The mitzvah (commandment) against testing Yahweh did not apply to Yahweh's command to Ahaz and, in fact, Ahaz broke it in resisting His commandments - thus indicting himself before the judgment of Israel's True King.

So instead of a sign to provide them victory and blessing, Yahweh would provide Ahaz with a sign of judgment - the signal that the rise and falling of many would be at hand.