Isaiah 7:14: "young woman" or "virgin"?
Almah means a young, marriageable woman. In the Tanakh it's used of unmarried young women, and the Jewish translators of the Septuagint chose "virgin" (parthenos) two centuries before Jesus.
This is a fair debate, and both sides have a point. Almah isn't the technical word for virgin (betulah). It describes a young woman of marriageable age.
But every other time almah appears where we can tell, it's an unmarried young woman: Rebekah (Genesis 24:43), Miriam as a girl (Exodus 2:8). And the Septuagint, translated by Jewish scholars in Alexandria around 250-150 BCE, renders it parthenos.
The bigger point: Isaiah calls this a sign to "the house of David", and the child's name is Immanuel, "God with us". Two chapters later the promised child is called "Mighty God" (9:5).
In the Scriptures
14לָ֠כֵן יִתֵּ֨ן אֲדֹנָ֥י ה֛וּא לָכֶ֖ם א֑וֹת הִנֵּ֣ה הָעַלְמָ֗ה הָרָה֙ וְיֹלֶ֣דֶת בֵּ֔ן וְקָרָ֥את שְׁמ֖וֹ עִמָּ֥נוּ אֵֽל׃
14Therefore the Lord Himself shall give you a sign: behold, the young woman shall conceive, and bear a son, and shall call his name Immanuel.
Isaiah 7:14 (Hebrew & JPS 1917)
43הִנֵּ֛ה אָנֹכִ֥י נִצָּ֖ב עַל־עֵ֣ין הַמָּ֑יִם וְהָיָ֤ה הָֽעַלְמָה֙ הַיֹּצֵ֣את לִשְׁאֹ֔ב וְאָמַרְתִּ֣י אֵלֶ֔יהָ הַשְׁקִֽינִי־נָ֥א מְעַט־מַ֖יִם מִכַּדֵּֽךְ׃
43behold, I stand by the fountain of water; and let it come to pass, that the maiden that cometh forth to draw, to whom I shall say: Give me, I pray thee, a little water from thy pitcher to drink;
Genesis 24:43 (Hebrew & JPS 1917)
The almah will bear a son: Immanuel A child born: Mighty God Ask about it
Sources
- Septuagint, Isaiah 7:14 (parthenos)
- Genesis 24:43; Exodus 2:8
- Rashi on Isaiah 7:14