At the time of Mary’s pregnancy, the idea of a virgin birth was not completely foreign to the Jews’ understanding of their Scripture. Although they misinterpreted it, many of the rabbis exegeted Jeremiah 31:22 (“a woman shall encompass a man”) in a way that suggested the Messiah would have an unusual birth. Their fanciful explanation of that verse (“Messiah is to have no earthly father,” and “The birth of Messiah shall be like the dew of the Lord, as drops upon the grass without the action of man”) at least preserved the general idea that the Messiah’s birth would be unique.

Actually the Book of Genesis gives us the first glimpse that Christ’s birth would be special: “‘And I will put enmity between you and the woman, and between your seed and her Seed’” (Genesis 3:15). Technically, the woman’s seed belongs to the man, but Mary’s impregnation by the Holy Spirit is the only instance in history that a woman had a seed within her that did not originate from a human man.

The later divine promise to Abraham concerned his “descendants” (Hebrew, “seed”; Genesis 12:7), a common Old Testament way of referring to offspring. The unique reference in Genesis 3:15 to “her Seed” looks beyond Adam and Eve to Mary and to Christ. The two seeds of that verse can have a twofold emphasis. First, they can primarily refer to all people who are part of Satan’s progeny and all who are part of Eve’s. The two groups constantly wage spiritual war against each other, with the people of righteousness eventually defeating the people of evil. Second, the word translated “Seed” can be singular and refer mainly to one final, glorious product of a woman—the Lord Jesus Himself, born without human seed. In that sense the prophecy is definitely Messianic.

Matthew 1:22–23 clearly identifies Jesus’ virgin birth as a fulfillment of Old Testament prophecy: “So all this was done that it might be fulfilled which was spoken by the Lord through the prophet, saying: ‘Behold, the virgin shall be with child, and bear a Son, and they shall call His name Immanuel,’ which is translated, ‘God with us.’” Matthew’s quotation here of Isaiah 7:14 confirms that the prophet did in fact predict the virgin birth of Jesus Christ.

The prophet Isaiah made this momentous prophecy during the reign of Judah’s wicked and idolatrous King Ahaz. The king faced a major military threat from the Israelite king, Pekah; and the Syrian king, Rezin; both of whom wanted to overthrow Ahaz and replace him with a more compliant monarch. Instead of seeking the Lord’s help during that crisis, King Ahaz turned to Tiglath-Pileser, the brutal ruler of the pagan Assyrians. Ahaz even induced their assistance by offering them gold and silver stolen from God’s Temple.

Ahaz refused to listen to Isaiah’s report that God would deliver the people from Pekah and Rezin. Therefore the prophet spoke the remarkable prophecy of Isaiah 7:14, which told Ahaz that no one would destroy the people of God or the royal line of David. And sure enough, although Tiglath-Pileser destroyed the northern kingdom (Israel), deported its population, and overran Judah four times, God ultimately preserved His people just as He promised.

Isaiah also said that before another child (Maher-Shalal-Hash-Baz) was very mature or aware of events, the territories of Rezin and Pekah would be abandoned (Isa. 7:15–16). Again, the prophet’s divinely inspired words were completely accurate. Before the other child, who was born to Isaiah’s wife, was three years old, the two enemy kings were dead. Just as God fulfilled that ancient prophecy about Isaiah’s son, so He was about to fulfill the one concerning the virgin birth of the Lord Jesus Christ. Both were signs from the Lord that He would not abandon His people, but the greatest of the two was obviously the second one: that His Son would actually be born of a virgin, live among His people, and die for their sins.

In his original pronouncement in 7:14, Isaiah used the Hebrew word ’alma for “virgin.” That is a significant term, and it’s important to understand why the prophet used it. ’Alma occurs six other times in the Old Testament (Genesis 24:43; Exodus 2:8; Psalm 68:25; Proverbs 30:19; Song of Solomon 1:3; 6:8), and in each instance it connotes or denotes “virgin.” Until recent times, both Jewish and Christian scholars always translated the word that way.

It is interesting that in modern Hebrew either ’alma or betula can mean “virgin.” However, Isaiah did not use betula because in Old Testament Hebrew it can refer to a married woman who is not a virgin (Deuteronomy 22:19; Joel 1:8). It’s apparent, therefore, that he used ’alma in 7:14 with the clear, precise conviction that the woman who would bear the Messiah would indeed be a young woman who never had sexual relations with a man.

Matthew’s use of Isaiah’s prophecy followed directly in the prophet’s path. The apostle was not giving ’alma a Christian “twist” to make its usage fit a theory of the virgin birth. Instead, Matthew gave the term the same meaning as Isaiah intended, demonstrated by his translation of ’alma with the Greek parthenos, the same word used by the Jewish translators of the Greek Old Testament.

Although the credibility of the virgin birth does not rest solely on the use of a Hebrew word, a general understanding of the background and usage of ’alma strengthens our belief in Christ’s unique birth. It also helps us to see that Matthew, under the inspiration of the Holy Spirit, knew exactly what he was doing when he related Isaiah 7:14 to the birth of Jesus and declared again the equally amazing truths that “the virgin shall be with child, and bear a Son, and they shall call His name Immanuel.” In His virgin birth, Christ was, in the most literal sense, the Son who was “God with us.”