“Ask a sign of the LORD your God; let it be deep as Sheol or high as heaven.”
11. Either in the deep. I understand it simply to mean Either above or below. He allows him an unrestricted choice of a miracle, to demand either what belongs to earth or what belongs to heaven. But perhaps in the word deep there is something still more emphatic; as if he had said, “It belongs to you to choose.
Here, I. God, by the prophet, makes a gracious offer to Ahaz, to confirm the foregoing predictions, and his faith in them, by such sign or miracle as he should choose (Isa 7:10, Isa 7:11): Ask thee a sign of the Lord thy God; See here the divine faithfulness and veracity. God tells us nothing but what he is able and ready to prove.
Commenting on Isaiah 7:10-16
Ask thee a sign of the Lord thy God,.... For though Ahaz was a wicked man, yet the Lord was his God, as he was the God of the people of Israel in general, as a nation; and knowing his unbelief and diffidence of his word unto him, offers to confirm it by a sign or miracle: ask it either in the depth, or in...