(Isa. 7:10–12; D&C 63:10; refer in Latter-day Commentary on the Book of Mormon, Bassett, to Alma 30:43)
Ahaz’s disbelief is indicated in Isaiah 7:9, and verse 11 is further evidence of his reluctance to follow the admonition of the Lord. The Lord challenges him to ask for a sign “either in the depth, or in the height above.” The RSV renders this phrase “let it be deep as Sheol or high as heaven.” In other words, let it be from the spirit world or from God in heaven. Ahaz gives an interesting rationalization for his refusal, quoting Deuteronomy 6:16 to justify his actions. The irony of quoting a scripture out of context in refusing to follow the prophet of the Lord further exemplifies his disbelief.
(Monte S. Nyman, Great Are the Words of Isaiah [Salt Lake City: Bookcraft, 1980], 56.)