Quoted from Isaiah 7:14. This quotation is closer to the Septuagint than the Hebrew text. The word in the Hebrew text which gets translated “virgin” means “young woman,” not specifically “virgin.” Thus, Isaiah 7 spoke of a “young woman” being pregnant, and furthermore, at that very time, not more than 700 years later: “Therefore the Lord himself will give you a sign. Look, the young woman is with child and shall bear a son, and shall name him Immanuel. He shall eat curds and honey by the time he knows how to refuse the evil and choose the good. For before the child knows how to refuse the evil and choose the good, the land before whose two kings you are in dread [Syria and Israel] will be deserted” (Isa. 7:14-16; and historically, Syria and Israel were both shortly attacked by Assyria and conquered).
The prophecy and immanent fulfillment of Isaiah 7 during Isaiah’s time is why even very spiritual Jews like Joseph and Mary were not expecting a virgin birth. When the angel told Mary that she was going to give birth to the Messiah, she was very surprised that it was going to be a virgin birth. She said to the angel, “How will this be, seeing I am not knowing [not currently having sex with] a man” (Luke 1:34).
When the Hebrew text was translated into Greek about 250 BC, making the version we know as the Septuagint, the translators translated the Hebrew word almah (#05959 עַלְמָה), “young woman,” as parthenos (#3933 παρθένος). The Hebrew word almah refers to a “young woman” but not necessarily a virgin. Similarly, there is good evidence in the Greek literature that the word parthenos does not specifically refer to the virginity of the woman or man. Rather it refers more to their age as being young (parthenos with the masculine pronoun refers to a young man). The Liddell & Scott Greek-English Lexicon gives references when parthenos was used of young married women. Also, some scholars say that if strictly “virgin” was meant, then parthenois would have been used instead of parthenos (see note in The Source New Testament by A. Nyland). That the Septuagint read parthenos in Isaiah 7:14, but the Jewish people did not think their Messiah would be born of a virgin, is quite conclusive evidence that the word parthenos did not have to refer to a virgin, even though it could refer to one.
Mary was certainly a young woman, thus an almah and a parthenos, and she was also a virgin. We know she was a virgin, not from the meaning of the word parthenos, but from the clear statements in both Matthew and Luke, and Mary is referred to as a parthenos in both Matthew and Luke.
Many commentators have written about Isaiah 7:14 and how the vocabulary and the context are not about a virgin birth but about a birth that would occur in Isaiah’s time, and that is true. Easily available commentaries include J. P. Lange’s Commentary and the commentary on the Old Testament by Keil and Delitzsch. English versions such as the Revised Standard Version read “young woman” instead of “virgin” in Isaiah 7:14, and that is the proper way to translate the Hebrew text (other versions that read “young woman” include: BBE, CJB, NAB, NET, NJB, NRSV, RSV, The Complete Bible: An American Translation; and the Moffatt Bible).
We can tell from Matthew that the prophecy in Isaiah, which referred to a young woman, had a second fulfillment in Jesus Christ. We must remember that it is God who prophetically tells the future, and God can shape His prophecies so that they fit multiple situations, even if unbelievers or over-zealous Christians deny a double fulfillment. Interestingly, unbelievers usually agree that the prophecy was fulfilled in Isaiah’s time and deny the fulfillment in Matthew, while over-zealous Christians deny the fulfillment in Isaiah’s time and invent reasons why the only fulfillment is with the birth of Christ.
When it comes to Isaiah 7:14, it is like Hosea 11:1 in that it involved two fulfillments. What we should be aware of when it comes to prophecies that are fulfilled twice, is that once it is fulfilled the first time, the only way people can see a second fulfillment is if God tells them about it, like He does with Isaiah 7:14 or Hosea 11:1. A good, but technical treatment of Isaiah 7:14 is in The Bible Translator, July 1958, “A Study of Isaiah 7:14,” by Robert G. Bratcher.
It fits perfectly within the scope and purpose of the Book of Isaiah that the prophecy in Isaiah 7:14 would have a second fulfillment in the birth of Jesus Christ, because Isaiah and his children are specifically said to be “signs” (Isa. 8:18). Just as the prophet Isaiah foretold the birth of a son who would be born in his own time and be associated with the deliverance of Judah, so the prophecy also was fulfilled by a son who would be born centuries later who was associated with the ultimate deliverance of Judah.
As the New Testament makes clear in Matthew and Luke, Mary was impregnated by God. In fact, the very reason Isaiah is quoted in this context is because it is the second and ultimate fulfillment of the prophecy in Isaiah. That is why Matthew 1:22 opens with, “Now all this happened to fulfill” the words of Isaiah. If Mary’s having a son did not fulfill Isaiah, then it would not have been appropriate to quote it as Matthew quoted it. Matthew 1:22 shows that Mary’s being impregnated by God fulfilled the prophecy in Isaiah 7:14.
“Look!” The Greek word is idou (#2400 ἰδού), and it is used to get our attention. Although the literal meaning of idou relates to visual perception (seeing), it was used idiomatically, and thus should be translated in ways appropriate to the context, such as “look,” “listen,” “pay attention,” “consider,” “remember,” etc. Many translations of the English Bible (cp. NIV, NRSV, HCSB) do not translate idou, but in doing so miss the meaning that it is bringing to the context. See commentary on Matthew 1:20 (“Look!).
“Immanuel.” One of the names of Jesus Christ is “Immanuel,” which can be translated as, “God with us” or “God is with us.” We know that God was with us in Jesus Christ, and Jesus himself said that if one had seen him, he had seen the Father. Names are often symbolic, the meaning of the name importing some characteristic that God wants us to know. When Jesus is called the Lion of Judah, the Lamb, or the tent peg (Zech. 10:4), God is importing characteristics about Jesus that He wants us to know. When it comes to Immanuel, God wants us to know that through Jesus Christ, God was with us. Not with us literally, but acting powerfully through His Son, just as 2 Corinthians 5:19 indicates: “That God was in Christ, reconciling the world to Himself.” It is important to read exactly what was written: God was in Christ, not God was Christ.
Symbolism in names can be seen throughout the Bible, it is not something that is unique to Jesus Christ. Many people were given names that would cause great problems if they were believed literally. Are we to believe that Bithiah, a daughter of Pharaoh, was the sister of Jesus because her name is “daughter of Yahweh?” Are we to believe that Eliab was the real Messiah since his name means “My God [is my] father?” Of course not. It would be a great mistake to claim that the meaning of a name proves a literal truth. We know that Jesus’ name is very significant—it communicates the truth that, as the Son of God and as the image of God, God is with us in Jesus, but the name does not make Jesus God. For more on this point, see Graeser, Lynn, and Schoenheit, One God & One Lord, and the website: BiblicalUnitarian.com. Also, A. Buzzard and C. Hunting, The Doctrine of the Trinity; Patrick Navas, Divine Truth or Human Tradition; D. Snedeker, Our Heavenly Father Has No Equals.
(which translated, means, “God with us”). The parenthesis is the figure of speech epitrechon, a form of parenthesis where the statement is not itself a complete thought (Bullinger, Figures of Speech).