(Isa. 7:14–16; refer in this text to 2 Ne. 18:18)
Isaiah and others often spoke in figures, using types and shadows to illustrate their points. Their messages were, in effect, hidden in parables (2 Ne. 25:1–8).
For instance, the virgin birth prophecy is dropped into the midst of a recitation of local historical occurrences so that to the spiritually untutored it could be interpreted as some ancient and unknown happening that had no relationship to the birth of the Lord Jehovah into mortality some 700 years later.
(Bruce R. McConkie, Ensign, Oct. 1973, 82–83.)
This sign was given to the Old Testament King Ahaz, encouraging him to take his strength from the Lord rather than military might of Damascus, Samaria, or other militant camps. Ahaz was slow to hear that counsel, but the Lord gave it anyway, declaring one of the signs to be a virgin’s conception and birth of a son whose name would be called Immanuel.
There are plural or parallel elements to this prophecy, as with so much of Isaiah’s writing. The most immediate meaning was probably focused on Isaiah’s wife, a pure and good woman who brought forth a son about this time, the child becoming a type and shadow of the greater, later fulfillment of the prophecy that would be realized in the birth of Jesus Christ. The symbolism in the dual prophecy acquires additional importance when we realize that Isaiah’s wife may have been of royal blood, and therefore her son would have been royalty of the line of David. Here again is a type, a prefiguration of the greater Immanuel, Jesus Christ, the ultimate son of David, the royal King who would be born of a literal virgin. Indeed, his title Immanuel would be carried forward to the latter days, being applied to the Savior in section 128, verse 22 of the Doctrine and Covenants.
(Jeffrey R. Holland, Christ and the New Covenant [Salt Lake City: Deseret Book Co., 1997], 79.)
Now if Immanuel of verse 14 is the Messiah, the Savior, what is his connection with the “child” of verses 15 and 16? Many Jewish commentators, not to mention some non-Jewish ones, think that the “virgin” or “young woman” of verse 14 may be a woman of the royal family, or any other young woman of Judah, and that her son, a boy whom she called Immanuel, does not refer to the Christ. Personally, I am inclined to accept Immanuel as a reference to the Savior, and especially in the light of [Isa. 8:8], where Judah is referred to as Immanuel’s land. The allusion to Immanuel suggests that the land of Judah (about which Ahaz was concerned) had a great destiny to fulfill, and hence that it was not about to be destroyed by Syria and Ephraim. Verses 15 and 16 of [Isaiah 7] simply make our Lord’s infancy a symbolical representation of the short-lived nature of the threat to Judah.
(Sidney B. Sperry, Book of Mormon Compendium [Salt Lake City: Bookcraft, 1968], 199.)
Isaiah, then, declared that the Lord would, nevertheless, give him a sign: Behold, a virgin—a young wife, possibly the wife of the Prophet—would become the mother of a son, whom she would call Emmanuel, meaning, “God is with us.” Syria and the land of Ephraim. Both would be overrun by the Assyrians before the child would be old enough to discern between evil and good. This prophecy was literally fulfilled in the days of Ahaz, but it had another fulfillment in the person of our Lord. According to Matthew 1:20–24, Joseph, when thinking of leaving Mary secretly, without causing a public scandal, had a dream, in which an angel appeared to him and explained that he had no cause against Mary. The evangelist adds that, all this was done, that it might be fulfilled which was spoken of the Lord by the Prophet, saying: “Behold, a virgin shall be with child, and shall bring forth a son, and they shall call his name Emmanuel.” A most notable instance of the double application of a prophetic utterance!
(George Reynolds and Janne M. Sjodahl, Commentary on the Book of Mormon, ed. Philip C. Reynolds, 7 vols. [Salt Lake City: Deseret Book Co., 1955–1961], 1:342.)
Within the prophetic context, any act of divine deliverance foreshadows God’s ultimate deliverance—salvation. Therefore, there should be no problem in seeing how God used the birth of a baby in Isaiah’s time to foretell deliverance for that generation, while focusing attention on the birth of another baby, through whom all the world will be delivered (Isa. 9:6). And Isaiah himself was chosen by the Lord to be the father, just as the faithful witness recorded (Isa. 8:1–3, 18). How honored Isaiah must have felt when his own son was called to typify the birth of God’s own Son… . Indeed, the Lord’s message of deliverance is contained in their names: “Isaiah,” Hebrew yesa’yahu, means “Jehovah saves.” “Maher-shalal-hash-baz” (Isa. 8:1) represents an earthly deliverance that points to salvation, and “Shear-jashub” (Isa. 7:3) means “a remnant will return.”
(Keith A Meservy, Studies in Scripture, Vol. 4, ed. Kent P. Jackson, [Salt Lake City: Deseret Book Co., 1993], 97.)